UNIVERSITY  OF  CALIFORNIA. 


JIOLOGY 

1BRARY 

G 


FROM   THE    LIBRARY  OF 

DR.  JOSEPH    lECONTE, 
GIFT  OF  MRS.  LECONTE. 

No. 


A    NEW    DICTIONARY 

OF 

MEDICAL  SCIENCE  AND  LITERATURE. 


LEA  AND  BLANCHARD, 

SUCCESSORS  TO  CAREY  AND  CO., 

Have,  recently  published 

A    NEW    EDITION, 

Completely  Revised,  with  Numerous  Additions  and  Improvements, 

OF 

DUNGLISON'S   DICTIONARY 

OF 

MEDICAL«    SCIENCE    AND    LITERATURE: 

CONTAINING 

A  concise  account  of  the  various  Subjects  and  Terms,  with  a  Vocabulary  of 
Synonymes,  in  different  languages,  and  formulae  for  various  officinal  and  em- 
pirical preparations,  &c. 

IN  ONE  ROYAL  8vO.  VOLUME. 

"  This  is  an  excellent  compilation,  and  one  that  cannot  fail  to  be  very  much 
referred  to.  It  is  the  best  medical  lexicon  in  the  English  language  that  has  yet 
appeared.  We  do  not  know  any  volume  which  contains  so  much  information  in 
a  small  compass.  The  Bibliographical  notices,  though  so  short,  are  very  impor- 
tant and  useful;  and  altogether  we  can  recommend  to  every  medical  man  to  have 
this  work  by  him,  as  the  cheapest  and  best  dictionary  of  reference  he  can  have." 
London  Medical  and  SurgicalJournaL 

A  NEW  WORK  ON  PHYSIOLOGY. 

OUTLINES  OF  PHYSIOLOGY, 

WITH 

AN  APPENDIX  ON  PHRENOLOGY: 

BY    P.    M.    R  O  G  E  T,   M.  D. 

Professor  of  Physiology  in  the  Royal  Institute  of  Great  Britain,  $c.  §c, 

FIRST  AMERICAN  EDITION. 

Revised,  with  numerous  notes. 

IN  ONE  VOLUME,  8vO. 

"  A  luminous  and  most  candid  and  impartial  account  of  Phrenology.  In  the 
treatise  on  Physiology,  that  science  is  treated  clearly,  fully,  and  in  the  systematic 
manner  which  a  masterly  instructer  might  adopt  for  the  benefit  of  his  pupils.1' 
Tail's  Magazine, 

"  Simply  viewed  as  a  modern  physiological  work  containing  all  that  is  valua- 
ble, and  even  excellent  in  other  productions  of  the  same  kind  which  have  pre- 
ceded it — embracing  a  vast  amount  of  curious  facts  in  comparative  anatomy — we 
cannot  withhold  the  expression  of  warm  approbation  of  this  work.  We  have 
derived  both  pleasure  and  instruction  from  its  pages.  It  should  be  in  the  hands 
of  every  medical  student,  and  in  all  medical  libraries.." — Boston  Medical  and 
Surgical  Journal. 


A  NEW  AND  VALUABLE  WORK  FOR  PHYSICIANS, 
APOTHECARIES,  AND  STUDENTS. 

NEW  REMEDIES — The  method  of  preparing-  and  administering  them — their 
effects  on  the  Healthy  and  Diseased  Economy,  &c.,  by  Robley  Dunglison,  M.  D., 
Professor  of  the  Institutes  of  Medicine,  and  Materia  Medica  in  Jefferson  Medical 
College  of  Philadelphia;  attending  Physician  to  the  Philadelphia  Hospital,  &c. 
&c. — In  1  vol.  8vo. 


NEW  EDITIONS 
Of  the  following  works  revised  and  corrected  by  the  Authors. 

DEWEES  ON  THE  DISEASES  OF  CHILDREN.     Seventh  edition.     In 

1  vol.  8vo. 


DEWEES  ON   THE  DISEASES    OF  FEMALES,— Seventh  edition,  with 
many  Additiens.     In  1  vol.  8vo. 


A  COMPENDIOUS  SYSTEM  OF  MIDWIFERY;  chiefly  designed  to  facili- 
tate the  Inquiries  of  those  who  may  be  pursuing  this  Branch  of  Study.  By 
W.  P.  DEWEES,  M.  D.  In  1  vol.  8vo.  with  13  plates.  Ninth  edition,  cor- 
rected and  enlarged. 


A  NEW  EDITION  OF  GIBSON'S  SURGERY. 

THE  INSTITUTES  AND  PRACTICE  OF  SURGERY;  being  the  Outlines 
of  a  Course  of  Lectures.  By  WILLIAM  GIBSOX,  M.  D.,  Professor  of  Surgery 
in  the  University  of  Pennsylvania,  &c.  &c.  Fifth  edition,  greatly  enlarged. 
In  2  vols.  8vo.  With  thirty  plates,  several  of  which  are  coloured. 

"  The  author  has  endeavoured  to  make  this  edition  as  complete  as  possible,  by 
adapting  it  to  the  present  condition  of  surgery,  and  to  supply  the  deficiencies  of 
former  editions  by  adding  chapters  and  sections  on  subjects  not  hitherto  treated 
of.  And,  moreover,  the  arrangement  of  the  work  has  been  altered  by  trans- 
posing parts  of  the  second  volume  to  the  first,  and  by  changing  entirely  the  order 
of  the  subject  in  the  second  volume.  This  has  been  done  for  the  purpose  of 
making  the  surgical  course  in  the  university  correspond  with  the  anatomical  lec- 
tures, so  that  the  account  of  surgical  diseases  may  follow  immediately  the  anato- 
my of  the  parts." 


THE  PRACTICE  OF  PHYSIC.  By  W.  P.  DEWEES,  M.  D.,  Adjunct  Pro- 
fessor  of  Midwifery,  in  the  University  of  Pennsylvania.  New  edition,  greatly 
enlarged.  Complete  in  1  vol.  8vo. 

"  We  have  no  hesitation  in  recommending  it  as  decidedly  one  of  the  best  sys- 
tems of  medicine  extant.  The  tenor  of  the  work,  in  general,  reflects  the  highest 
honour  on  Dr.  Dewees's  talents,  industry,  and  capacity  for  the  execution  of  the 
arduous  task  which  he  had  undertaken.  It  is  one  of  the  most  able  and  satisfactory 
works  which  modern  times  have  produced,  and  will  be  a  standard  authority."— 
London  Med.  and  Surg.  Journ.  Aug.  1830, 


TREATISE 


ON 


SPECIAL    AND     GENERAL 

ANATOMY. 

BY  WILLIAM  E.  HORNER,  M.  D. 

PROFESSOR    OF  ANATOMY  IN  THE    UNIVERSITY   OP    PENNSYLVANIA— MEMBER    OF  THB   IMPERIAL 

MKDICO-OHIRURQICAL  ACADEMY  OF  ST.  PETERSBURG— OF  THE 

AMERICAN  PHILOSOPHICAL  SOCIETY,  &C. 


Multum  adhuc  restat  operis,  multumque  restabit,  nee  ulli  nato,  post  mille  ssecula 
pnecluditur  occasio  aliquid  adjiciendi. 

SENECA,  EPIST. 


IN  TWO  VOLUMES. 
VOL.  I. 

FIFTH  EDITION,  REVISED  AND  IMPROVED. 


LEA    &    BLANCHARD, 

SUCCESSORS  TO  CAREY  &  CO. 

1840, 


BIOLOGY 

LIBRARY 

G 


Eastern  District  of  Pennsylvania,  to  wit: — 

BE  IT  REMEMBERED,  that,  on  the  seventeenth  day  of  October,  in  the 
fifty-first  year  of  the  Independence  of  the  United  States  of  America,  A.  D. 
1826 — William  E.  Homer,  of  the.  said  district,  hath  deposited  in  this  office  the 
title  of  a  book,  the  right  whereof  he  claims  as  Author,  in  the  words  following-, 
to  wit: — 

"  A  Treatise  on  Special  and  General  Anatomy.  By  William  E.  Homer,  M.  D. 
Adjunct  Professor  of  Anatomy  in  the  University  of  Pennsylvania,  Member  of 
the  American  Philosophical  Society — Surgeon  at  the  Philadelphia  Alms 
House,  &c.  '  '  Multum  adhuc  restat  operis,  multumque  restabit,  nee  ulli  nato, 
post  mille  saecula  prsecluditur  occasio  aliquid  adjiciendi.'  Seneca,  Epist.  In 
two  volumes.'  Vol.  II. 

In  conformity  to  the  Act  of  the  Congress  of  the  United  States,  entitled,  "  An 
Act  for  the  Encouragement  of  Learning,  by  securing  the  Copies  of  Maps, 
Charts,  and  Books,  to  the  Authors  and  Proprietors  of  such  Copies,  during  the 
times  therein  mentioned" — And  also  to  the  Act,  entitled  "An  Act  supplemen- 
tary to  an  Act,  entitled,  '  An  Act  for  the  Encouragement  of  Learning,  by  se- 
curing the  Copies  of  Maps,  Charts,  and  Books,  to  the  Authors  and  Proprietors 
of  such  Copies,  during  the  times  therein  mentioned,'  and  extending  the  bene- 
fits thereof  to  the  arts  of  designing,  engraving,  and  etching  Historical  and  other 
Prints." 

D.  CALDWELL, 
CJerk  of  the  Eastern  District  of  Pennsylvania. 


&  CO.,  PIUJTTEnS. 


PREFACE 

To  the  First  Edition,  published  in  1826. 


THE  many  additions  that,  of  late  years,  have  been 
made  to  Descriptive  or  Special  Anatomy;  the  improved 
views  on  the  collocation  of  its  objects;  the  alterations  and 
amendments  in  the  method  of  description;  and  the  non- 
urgent call  for  some  greater  information  on  General  Ana- 
tomy than  what  is  commonly  introduced  into  the  scho- 
lastic systems;  require  in  the  English  language,  for  the 
benefit  of  the  medical  student  and  of  the  practitioner,  a 
new  work  on  the  structure  of  the  body,  executed  by  one 
who  is  in  the  habit  of  pursuing  anatomical  inquiries  by 
constant  dissection.  It  would  have  been  pleasant  to  me 
if  some  gentleman,  whose  time,  opportunities,  qualifica- 
tions, and  spirit  ofresearch  were  better  suited  to  the  en- 
terprise, had  stepped  forward  for  its  accomplishment. 
While  meditating  on  this  subject,  I  had  a  strong  desire 
to  remodel  the  excellent  work  of  Dr.  Wistar,*  on  a  plan 
more  suited  to  the  actual  state  of  the  science ;  but,  upon 
reflecting  that  it  was  a  justly  celebrated  monument  to 
his  reputation,  I  became  dissatisfied  with  the  project  of 
cutting  and  carving  it  into  a  more  modern  figure.  In 
addition  to  which  consideration,  having  frequently  de- 
parted from  his  authority,  the  alternative  was  presented 
either  of  suppressing  his  ideas  to  substitute  my  own,  or 
of  giving  currency  to  opinions  differing  from  my  own 
convictions,  neither  of  which  was  agreeable.  The  la- 

*  A  system  of  Anatomy  for  the  use  of  Students  of  Medicine. — 
Philadelphia,  1817. 


IV  PREFACE. 

hour,  moreover,  of  remodelling  would  have  been  almost 
equal  to  the  writing  cf  a  new  book. 

Neither  is  there  any  work  extant  from  the  British 
press,  which  presents  a  good  model  for  a  body  of  Ana- 
tomy.    This  assertion  may  surprise  some,  and  yet  it 
is  entirely  true,  and  especially  so  in  regard  to  the 
British  publications  most  circulated  in  this  country : 
I  allude  to  the  Anatomy  of  Mr.  Fyfe,*  and  to  that  of 
Mr.  Bell.f     The  first,  from  being  unpretending,  good 
in  its  way,  and  having  accomplished  the  object  for  which 
it  was  intended;  to  wit,  as  a  general  outline  of  anatomi- 
cal objects,  requires  for  the  present  no  farther  comment. 
But  the  second,  being  presented  to  us  in  the  imposing 
form  of  four  octavo  volumes ;  illustrated  by  numerous 
diagrams  and  plates;  abounding  in  strictures  upon  the 
opinions  of  others,  and  written  in  a  fanciful  pleasant 
manner;  has  had  a  much  more  powerful  influence  on 
the  taste  of  the  American  student,  and  is,  therefore,  a 
very  proper  subject  for  a  short  analysis.   It  is  not  going 
beyond  bounds,  when  I  say,  that  there  is  no  work  which 
affords  more  amusement  to  the  young  student  on  the 
first  perusal,  or  whose  authority  is  viewed  by  him  with 
more  deference.    Its  sprightly  style;  its  confident  man^ 
ner  of  address;  the  many  exploded,  antiquated  errors 
which  have  been  disentombed  from  absolute  oblivion, 
in  order  to  make  the  reader  laugh  at  them;  the  gro- 
tesque dress  put  upon  the  valuable  opinions  of  others; 
and  their  travestied  doctrines;  all  contribute  to  make  it 
read  like  a  production  of  the  imagination,  and  to  have 

*  A  Compendium  of  the  Anatomy  of  the  Human  Body,  intended 
principally  for  the  use  of  Students.  Philad.  Ed.  1802. 

t  The  Anatomy  of  the  Human  Body,  illustrated  with  one  hundred 
and  twenty-six  engravings.  By  John  Bell,  Surgeon. 


PREFACE.  V 

the  same  sort  of  popularity  which  works  of  the  latter 
kind  frequently  enjoy.  As  the  real  importance,  how- 
ever, of  a  work  upon  an  exact  science  does  not  exist  in 
its  wit  and  "bizarreries"  but  upon  the  wholesomeness 
of  its  truths,  and  the  accuracy  with  which  they  are 
stated;  it  is  fair  to  expect  that  the  writer  should  himself 
be  faultless,  who  thus  uses  the  weakness  of  others  as 
the  foil  upon  which  to  display,  most  advantageously, 
his  own  presumed  brilliancy  and  perfection.  It  does 
not  require  much  scrutiny  to  ascertain  whether  the  ex- 
pectation is  realized,  and  whether  this  author  does  not 
abound  in  inaccuracies,  in  exaggeration,  in  obscurities, 
and  in  irrelative  matter. 

In  regard  to  the  inaccuracies  of  Mr.  Bell,  we  give  the 
following  as  specimens,  which  we  have  got  without  far- 
ther trouble  than  that  of  thumbing  his  pages.  "  This 
membrane  (the  Mediastinum)  passes  directly  across  the 
breast  from  the  sternum  before,  till  it  fixes  itself  in  the 
spine  behind.  It  is  on  the  left  side  of  this  membrane,  in 
the  left  cavity  of  the  breast,  that  the  heart  is  placed." 
"  The  Eustachian  Valve  is  in  general  thick  and  fleshy  " 
"The  Pericardium  is  formed,  like  the  Pleura  and  Me- 
diastinum, of  the  cellular  substance"  " The  Perioste- 
um is  merely  a  condensation  of  the  common  cellular  sub- 
stance, formed  in  successive  layers."  "The  perioste- 
um, tendons,  fasciae  and  burses  mucosce,  are  all  of  one 
substance  and  of  one  common  nature."  "  The  socket, 
(i.  e.  theacetabulum)  is  deepened  by  its  cartilage,  which 
tips  the  edge  of  the  socket,  and  stands  up  to  a  conside- 
rable height."  Some  of  these  mistakes  are  glaring  blun- 
ders; others  may  perhaps  be  referred  to  the  faulty  phra- 


Vlll  PREFACE. 

another,  like  vitriol  upon  tartar,  and  thereby  ejecting 
itself  through  the  aorta. — Of  side  passages  in  the  heart 
through  the  septum  of  the  ventricles. — Of  the  cele- 
brated general  of  the  Messenians,  Aristomenes,  known 
equally  well  for  his  devotion  and  constancy  to  the  cause 
of  his  countrymen,  having  his  heart  filled  with  hair,  a 
proof  of  his  invincible  courage  and  daring.  Of  the  eel 
which  was  found  in  the  heart  of  a  patient  of  Dr.  May. 
These  matters  may  possibly  be  excused  on  the  footing 
of  episodes,  intended  to  diminish  the  tediousness  of  a 
long  story. 

The  oddities  of  this  writer  are  likewise  entirely  cha- 
racteristic :  thus,  we  have  in  his  Principles  of  Surgery 
a  regular  diagram  of  the  resemblance  between  the  thigh 
bone  and  a  chariot  with  dished  wheels.  "Polonius. 
Very  like  a  whale." 

The  last  comment  which  we  have  to  make  touching 
this  "  popular  writer"  is  on  his  anatomical  illustrations. 
I  cannot  enter  into  an  analysis  of  them,  but  have  only 
time  to  say,  that  if  ever  a  simple  matter  was  perplexed 
by  illustrations,  we  have  this  feat  to  perfection  in  the 
account  of  the  Circulation,  of  Respiration^  and  of  the 
round  of  blood  in  the  Foetus.* 

The  character  of  the  preceding  vagaries  may  suit  a 
writer  on  common  literary  subjects,  where  amusement 
only  is  intended ;  but  is  totally  unfitted  to  an  instructor 
in  an  exact  science,  where  words  should  be  used  only 
according  to  their  technical  meaning,  and  where  patient 
observation  is  the  only  guaranty  from  ridiculous  mis- 

*  The  preceding  observations  are  principally  applicable  to  the  first 
and  second  volumes  of  the  Anatomy  of  the  Human  Body  ;  the  third 
and  fourth  have  been  executed  in  much  better  taste  by  Mr.  Charles 
Bell. 


PREFACE.  IX 

takes.  But  I  must  here  stop^  for  I  have  never  aspired 
to  the  reputation  of  a  critic,  and  to  the  equivocal  friend- 
ship with  the  rest  of  the  world  which  such  commenta- 
tors generally  have.  I  have  only  been  induced  to  point 
out  these  faults,  because  it  appeared  to  me  that  the 
writer  alluded  to/though  now  numbered  with  the  dead, 
has  left  a  reputation  tending  to  deprave  the  scientific 
habits  of  such  medical  students,  and  they,  I  believe, 
are  not  a  few,  as  read  his  works.  I  am  also  checked 
by  the  hint  of  Le  Sage :  "En  verite  sil  y  a  bien  de  mau- 
vais  auteurs,  il  faut  convenir  q'il  y  a  encore  plus  de 
mauvais  critiques."*  I,  therefore,  conclude  by  sug- 
gesting, that  if  an  exact  science  require  for  the  relief  of 
its  student  some  dilution  with  the  works  of  the  imagi- 
nation ;  instead  of  corrupting  it  with  mere  notions  and 
exaggerations,  it  would  be  much  better  for  the  student 
to  resort  to  productions  of  the  fif  st  merit,  and  to  hold  in 
one  hand  his  System  of  Anatomy,  and  in  the  other  a 
Milton,  or  a  Waverly  Novel. 

I  should  be  extremely  sorry  to  be  understood  as  doubt- 
ing the  capability  of  the  British  anatomists  to  write  a 
good  treatise  on  this  subject.  I  indeed  feel  persuaded 
of  the  contrary;  and,  therefore,  only  mean  that  as  yet 
they  have  not,  in  this  particular,  done  justice  to  them- 
selves, or  to  the  literary  reputation  of  their  country. 
Any  other  opinion  w^ould  be  great  injustice  to  them, 'and 
would  also  be  ingratitude  for  acts  of  friendship  and  civi- 
lity received  from  many  illustrious  and  enlightened  in- 
dividuals whom  the  profession  is  proud  to  own;  and  al- 

*  In  truth,  if  there  are  many  wretched  authors,  one  must  confess 
that  there  are  many  more  wretched  critics. — Gil  Bias. 


X  PREFACE. 

legiance  to  whose  doctrines  has,  moreover,  been  freely 
avowed,  in  the  present  work,  on  proper  occasions. 

To  the  profound  anatomist,  whose  inclinations  lead 
him  to  study  every  fasciculus  of  fibres  composing  a  mus- 
cle or  a  ligament,  and  every  minute  nervous  or  arterial 
ramification,  the.  present  Treatise  on  Anatomy  will  of 
course,  be  a  mere  outline  of  the  science.  But  to  the  stu- 
dent of  medicine  and  to  the  practitioner,  who  have  only 
time  to  dwell  upon  prominent  and  useful  points,  I  trust 
that  it  will  appear  sufficiently  full  for  most  professional 
objects.  The  anatomy  of  the  human  body  is  of  an  ex- 
tent much  beyond  the  common  conceptions  of  it,  and  is 
rather  a  generic  than  a  specific  term.  A  full  treatise 
on  it  would  contain  matter  to  twice  or  three  times  the  ex- 
tent of  the  present  work,  and  would  even  then  be  in 
many  respects  deficient;  for  it  must  not  only  give  a  full 
description  of  parts  in  the  adult  body,  but  their  first  ap- 
pearance in  foetal  life,  and  their  gradual  development 
into  the  perfect  or  adult  state.  It  must  also  contain  a 
complete  account  of  the  properties  of  each  kind  of  struc- 
ture composing  the  human  body,  called,  in  technical  lan- 
guage, General  Anatomy;  also  morbid  alterations  of 
structure,  and  finally  varieties  in  shape,  position,  &c. 

It  is  here  proper  to  remark,  that  though  every  hu- 
man body  be  formed  on  the  same  general  mould,  yet, 
in  examining  the  details  of  structure  in  an  individual, 
varieties  will  be  met  with  causing  a  difference  from 
all  other  individuals.  For  as  no  two  leaves  or  two  hu- 
man countenances  are  precisely  alike,  so  the  interior 
organs  of  individuals  differ  in  their  phases,  though  the 
same  end  is  obtained.  Hence,  it  becomes  necessary 


PREFACE.  XI 

for  a  system  of  anatomy  to  show  rather  what  is  of  the 
most  frequent  occurrence,  than  to  pretend  to  universal 
correctness;  because,  by  the  latter  test,  many  of  its  ac- 
counts are  inexact.  Some  of  these  departures  from  the 
general  rule  are  so  infrequent  as  to  deserve  the  name 
of  anomalies:  in  some  cases,  there  is,  indeed,  only  one 
or  two  recorded  instances;  but,  in  others,  the  variation 
is  so  frequent  as  to  leave  the  anatomist  in  doubt,  about 
what  mode  of  description  is  applicable  to  the  majority 
of  cases.  From  this  latter  cause,  we,  in  consulting 
different  writers,  sometimes  find  their  opinions  much 
opposed ;  and  to  our  surprise,  the  adage  of  quot  homines 
tot  sententics,  as  applicable  to  the  science  of  anatomy, 
as  it  is  to  one  of  an  abstract  and  confessedly  disputable 
kind.  Anatomy,  however,  in  its  great  outlines,  is  a 
science  surprisingly  and  sufficiently  exact;  the  excep- 
tions are  too  few  to  admit  of  hesitation  about  what  is 
right  and  what  wrong :  it  is,  therefore,  perhaps,  next  to 
mathematics  in  the  precision  of  its  indications,  and  in 
the  value  and  certainty  of  its  rules.  It  is,  for  these 
reasons,  in  every  way  suitable,  that  in  an  operation,  or 
in  the  treatment  of  a  disease,  where  the  condition  of 
organs  is  to  be  considered ;  that  we  should  look  with 
full  assurance  for  what  is  most  common,  rather  than  to 
hesitate  and  vibrate  between  two  opinions;  to  balk 
about  mere  varieties.  Otherwise,  a  knowledge  of  the 
possibility  of  the  latter  will  rather  injure  than  assist 
our  exertions,  and  our  inefficiency  will  have  the  ap- 
pearance and  effect  of  ignorance. 

Sensible  of  the  importance  of  reflecting  upon,  and 
of  observing  maturely  the  matters  treated  of,  I  have 


Xll  PREFACE. 

done  my  best  to  be  accurately  informed  by  repeated 
dissections,  and  .by  reference  to  the  highest  authorities. 
The  latter  was  happily  put  into  my  power,  by  the 
well-furnished  library  of  the  Alms  House  and  of  the 
Pennsylvania  Hospital;  and  by  a  private  collection, 
containing  many  of  the  most  approved  productions. 
This  balancing  of  the  opinions  of  others  with  one's 
own  dissections,  is,  unquestionably,  best  suited  to  cor- 
rect inferences :  to  follow  exclusively  the  one-  or  the 
other,  is  attended  with  great  liability  to  error.  An  un- 
due deference  to  approved  authorities  makes  our  opi- 
nions habitually  wavering  and  uncertain,  from  the 
discrepance  of  writers  among  themselves;  while  an  in- 
sufficient attention  to  such  means  of  information  pro- 
duces very  serious  mistakes  in  correctness  of  descrip- 
tion, and  very  false  ideas  of  scientific  acquirements. 
If  we  presume  on  our  own  infallibility  and  originali- 
ty, we  are  apt  to  suppose  ourselves  possessed  of  sur- 
passing skill,  as  floating  triumphantly  on  an  ocean  of 
discovery,  as  extending  in  every  direction  the  bounda- 
ries of  the  science  and  giving  a  new  impulse  to  it ; 
while,  on  the  contrary,  our  faulty  modes  of  examina- 
tion, and  neglect  of  competent  writers,  have  caused  us 
to  flounder  ridiculously  on  common-place  and  well 
settled  points.  It  is  thus  that  imaginary  originality  is 
not  unfrequently  in  an  inverse  proportion  to  the  recent- 
ness  of  one's  induction  into  the  science,  and  to  the  ex- 
actness with  which  it  has  been  studied. 

In  the  absence  of  knowledge,  the  young  and  enthu- 
siastic, but  heedless  anatomist,  is  frequently  prolific, 
from  the  commencement,  in  discoveries :  he  makes 


PREFACE.  Xlll 

them  in  such  numbers,  with  such  facility,  and  under 
such  unpremeditated  circumstances,  that  he  is  filled 
with  admiration  at  his  own  abilities  in  such  matters, 
and  at  the  ignorance  and  inattention  *of  his  predeces- 
sors and  cotemporaries.  In  the  ready  communication 
of  the  result  of  his  labours,  he  is  disposed  to  use  the 
language  of  high  attainment  and  of  advanced  reputa- 
tion. He  hints  at  his  anticipations  of  the  jealousy  and 
malice  which  are  known  to  follow  greatness  and  excel- 
lence; not  considering  that  there  is  quite  as  much 
proneness  in  an  individual  to  overrate  himself  from 
self-love,  as  there  is  in  others  to  decry  him  unjustly. 
He  feels  mortified  at  the  supposed  apathy  of  some  per- 
sons, and  indignant  at  others  for  not  placing  him  at 
once,  on  the  pinnacle  of  fame.  After  waiting  in  vain 
for  such  homage,  he,  at  length,  finds  out  that  the  mat- 
ters treated  of  have  all  the  triteness  of  being  very  well 
known;  or,  if  they  be  novelties,  they  are  the  offspring 
of  hasty  and  imperfect  observation,  and  were  rather 
leading  into  error  than  conducting  to,  the  truth.  An 
inattention  to  the  writings  of  others  has  also  the  incon- 
venience of  exposing  us  justly  to  the  raillery  and  cri- 
ticism of  persons,  who,  not  reflecting  that  it  is  scarcely 
possible  to  bring  new  truths  into  vogue,  much  less  er- 
rors, and  that  such  mistakes  carry  with  them  their  own 
seal  of  death,  they  drag  them  to  the  block,  there  to  die 
by  the  hand  of  the  public  executioner.  Dr.  W.  Hun- 
ter* has  justly  remarked,  that  "  He  that  is  in  a  hurry 
to  publish  his  discoveries,  will  often  have  occasion  to 
repent  his  haste.  Reflection,  and  more  favourable  op- 

*  Med.  Comment,  p.  57.     Lond.  1777. 
VOL.  L— 2 


XIV  PREFACE. 

port  unities  of  making  inquiries,  will  at  length  bring: 
us  back  to  the  truth,  if  we  have  been  misled,  and  will 
confirm  and  improve  our  inventions,  if  they  be  right." 
The  preceding^observations  are  not  intended  to  re- 
press the  spirit  of  generous  enterprise,  but  rather  to 
assist  it,  by  giving  it  a  proper  direction.  There  are, 
unquestionably,  many  things  yet  to  be  discovered  in 
anatomy,  as  proved  by  the  continued  contributions  of 
its  cultivators.  For,  in  the  language  of  the  motto, 
"  Multum  adhuc  restat  operis,  multumque  restabit, 
nee  ulli  nato,  post  mille  ssecula  prsecluditur  occasio 
aliquid  adjiciendi."  These  remarks  are  only  intended 
as  a  salutary  warning  to  the  young  votary  of  anatomy, 
not  rashly  to  promulgate,  by  boastful  writing  or  lan- 
guage, that  he  considers  his  own  acquisitions  as  the 
standard  of  the  science,  and  every  thing  beyond  them 
as  in  the  region  of  discovery.  Because,  if  he  does,  he 
is  sure  to  meet  with  the  most  mortifying  convictions 
to  the  contrary;  and  sometimes  to  find  himself  placed 
below  the  degree  of  his  actual  acquirements,  for  mani- 
festing a  want  of  acquaintance  with  topics  common  to 
others.  The  rule  is  undoubtedly  a  good  one:  "  Let 
not  him  that  putteth  on  his  harness  boast  himself,  as 

he  that  putteth  it  off." 

^ 

Nonthinking  that  the  present  treatise  is  a  proper 
field  for  discussion  on  controverted  points,  I  have  pur- 
posely, excepting  on  a  few  occasions,  avoided  it,  by 
simply  giving  an  opinion  after  my  own  views  of  cor- 
rectness, without  pretending  to  infallibility,  or  being 
disposed  to  reject  better  information  when  offered.  I 
cannot,  however,  but  feel  the  strongest  diffidence  of 


PREFACE.  XV 

my  powers  to  execute,  in  a  moderately  satisfactory, 
not  to  say  a  proper  manner,  the  enterprise  of  writing 
a  treatise  on  anatomy.  There  are  not  many  persons, 
who,  as  they  advance  in  the  study  of  the  science,  by 
dissections  and  by  reading,  do  not,  after  awhile,  as  in 
the  cultivation  of  high  religious  and  moral  attainments, 
mistrust  their  acquirements;  and  find,  that  whatever 
may  have  been  the  fancied  perfection  of  their  know- 
ledge during  the  infancy  of  their  studies,  they  were 
then  only  on  the  threshold  of  the  temple.  In  begin- 
ning the  career  of  anatomical  inquiries,  as  an  almost 
exclusive  profession,  we  have  yet  to  appreciate  the  la- 
bours; I  may,  indeed,  say  to  read  the  writings  of  the 
eminent  men  who  have  gone  before  us.  We  have  yet 
to  learn  the  infhiense  multitude  of  observations  by 
which  we  are  surrounded,  and  the  great  labour  that  it 
requires  to  master  them  all.  The  fact  is  well  esta- 
blished, that  it  requires  some  years  of  hard  study  be- 
fore the  anatomist  becomes  aware  of  his  own  weak- 
ness, and  of  the  many  things  that  he  has  yet  to  do  in 
order  to  be  brought  up  to  the  actual  state  of  the  sci- 
ence. 

Impressed  by  these  convictions,  I  have  constantly 
endeavoured  to  ascertain  and  present  the  science  of 
Descriptive  or  Special  Anatomy,  as  it  stands  at  the 
present  day,  \vithout  entering  into  all  the  minutiae  of 
details  of  which  it  is  susceptible.  I  have,  therefore, 
neglected  no  fact  bearing  on  the  subject,  which  seemed 
to  be  sufficiently  authenticated  or  important  to  deserve 
notice.  Owing,  however,  to  the  expanded  field  in 
which  I  have  worked,  and  the  many  pressing  engage- 
ments which  drew  my  attention  from  it,  it  is  not  im- 


PREFACE. 

probable  that  I  may  have  omitted  some  things  worthy 
of  remark,  which  I  may  have  subsequent  reason  to  re- 
pent my  neglect  of. 

By  far  the  greater  part  of  this  work  has  been 
wrought  up  in  regular  manuscript;  on  several  occa- 
sions, however,  not  wishing  to  make  the  text  more  pro- 
lix, I  have  incorporated  with  it  literal  extracts  from  my 
"  Lessons  in  Practical  Anatomy."  This  is  especially 
the  case  in  regard  to  the  nerves  of  the  extremities  and 
to  the  muscles.  The  two  works  harmonize;  yet  some 
unimportant  differences  may,  in  a  few  places,  be  ob- 
served by  the  attentive  reader,  owing  to  improved 
views  in  the  present.  Simple  typographical  mistakes 
have  also  given  rise  to  discrepancies ;  but  it  is  almost 
impossible  to  avoid  a  contingency  of  this  kind,  owing, 
sometimes,  to  the  inevitable  hurry  in  which  a  proof- 
sheet  is  corrected,  and,  at  others,  to  the  mechanical 
derangements,  to  which  the  press  is  subject. 

The  great  deficiency  of  the  English  language  in 
terms  suited  to  anatomical  description  and  nomencla- 
ture, and  the  difficulty  of  forming  suitable  compound 
words  from-it,  have  induced  me  to  take  some  liberties 
which  I  would  gladly  have  dispensed  with,  under 
other  circumstances.  To  avoid  periphrasis,  and  the 
inconvenient  repetition  of  sentences,  I  have,  therefore, 
frequently  adopted  French  terminations,  and  sometimes 
formed  a  word  upon  a  Greek,  a  Latin,  or  a  French 
root;  following,  in  these  respects,  the  authority  of  the 
Continental  Anatomists.  But  it  is  still  a  great  deside- 
ratum, for  anatomy  to  be  rather  more  algebraical  in  its 
characters  and  language,  than  it  is  at  present. 


PREFACE 

To  the  Fifth  Edition, 


THE  present  state  of  Anatomy  exhibits  the  propriety 
of  the  motto  adopted  for  the  title  of  this  work,  at  its 
first  edition  in  1826,  for  on  whatever  side  our  attention 
may  be  directed  to  the  nations  of  the  earth,  most  en- 
gaged in  the  cultivation  of  human  sciences  and  arts, 
we  find  that  Anatomy  is  still  in  progress,  and  will  pro- 
bably continue  so  to  the  end  of  time.  Contributions 
of  the  most  valuable  kind  have  been  made  in  France, 
in  Germany,  in  Italy,  and  in  England,  not  only  in  re- 
gard to  new  observations,  but  in  giving  a  greater  perfec- 
tion to  modes  of  elucidation  by  plates — models — draw- 
ings and  injections.  In  all  of  these  states,  improved 
systematic  treatises  have  appeared,  besides  numerous 
monographs  of  an  instructive  kind.  In  England  the 
science  has  taken  on  an  aspect  signally  amended  within 
the  last  twenty  years,  so  that  the  disparity  once  exist- 
ing between  her  and  the  states  of  the  continent,  strikes 
the  eye  of  the  inquirer  much  less  than  it  did  at  a  former 
period ;  in  fact  several  works  of  a  high  order  of  merit 
have  made  their  appearance.  Our  own  country  has 
manifested  the  same  spirit  of  advancement  in  the  in- 
crease of  medical  schools,  and  in  the  multiplication  of 
highly  instructed  teachers  of  anatomy,  and  expert  prac- 
tical anatomists.  Though  possessing  less  literary  and 
scientific  leisure  than  any  other  of  the  polished  and 

2* 


XV111  PREFACE. 

instructed  quarters  of  the  world ;  yet  those  limited  op- 
portunities have  been  fruitful  in  original  observations, 
in  translations,  in  papers,  in  monographs,  and  in  im- 
proved editions  of  preceding  works. 

The  several  productions  alluded  to  in  the  above 
sketch,  are  too  numerous  for  distinct  or  individual  no- 
tice on  the  present  occasion,  they  have,  however,  been 
freely  canvassed  for  the  composition  of  this  work,  and 
their  contribution  to  the  general  cause  of  anatomy 
claimed,  to  the  extent  that  it  could  be,  keeping  at  the 
same  time  this  work  within  the  precincts  of  what  it  is 
intended  for,  to  wit,  a  Text  Book  to  the  course  of  Lec- 
tures on  Anatomy  in  the  University  of  Pennsylvania. 
Some  things  may,  however,  be  omitted  as  useless,  which 
strike  the  understanding  of  others  as  too  important  for 
neglect;  and  other  things  on  the  ground  of  having  a  tes- 
timony too  defective,  at  present,  of  their  real  existence, 
to  justify  their  being  introduced  into  a  code  of  De- 
scriptive Anatomy. 

W.  E.  HORNER,  M.  D.,   Univ.  Penn. 
Philadelphia,  Oct.  1839. 


INTRODUCTION. 


THE  Science  of  Anatomy  has,  of  late  years,  been  di- 
vided into  Descriptive  and  General.  This  distinction, 
though  faintly  traced  by  preceding  anatomists,  owes  its 
present  prominence  to  the  labours  of  the  celebrated  Bi- 
chat;  and  the  daily  observations  of  physiologists  and  pa- 
thologists,  are  only  renewed  and  concurrent  evidences 
of  its  importance  and  value  in  the  practice  of  medicine. 
Although  the  distinction  is  only  coming  into  vogue  in 
this  country,  the  tendency  to  it  is  so  great  that  in  a 
few  years  more,  medical  language  and  ideas  will  be 
universally  tinged  with  it;  it  is  proper,  therefore,  that 
it  should  be  defined  in  such  a  manner,  that  it  may  be 
perfectly  intelligible  to  the  student. 

Descriptive  Anatomy  teaches  the  exterior  form  of  or- 
gans, their  magnitude,  their  position,  their  connexions 
with  adjacent  parts ;  and  their  intimate  texture  or  or- 
ganization. As  in  this  way  every  individual  part  is 
brought  under  a  strict  review,  it  is  this  division  of  the 
science  which  gives  skill  to  the  surgeon.  The  term  is 
not  entirely  appropriate,  because  description  means  any 
account  whatever ;  the  substitution  of  the  phrase  Special 
Anatomy  is,  therefore,  one  of  the  improvements  of  the 
present  day,  and  is  very  much  resorted  to. 

General  Anatomy  may  be  explained,  as  its  great 


XX  INTRODUCTION. 

founder,  Bichat,  himself  has  done  it,  by  the  following 
comparison.  Chemistry  has  its  simple  bodies,  as  heat, 
light,  hydrogen,  oxygen,  nitrogen,  carbon,  and  so  on, 
whose  several  combinations  form  all  the  composite  bo- 
dies on  the  face  of  the  globe.  In  the  same  way  anatomy 
has  its  simple  tissues,  whose  varied  combinations  form- 
all  the  organs  of  the  human  body  and  of  animals. 
These  tissues  are,* 

1.  The  Cellular,  Vol.  I.  p.  317 

2.  The  Adipose,  or  Medullary,  325 

3.  Vascular,  II.  p.  153,  280 

4.  Nervous,  313 

5.  Osseous,  I.  p.  56 

6.  Fibrous,  or  Desmoid,     -  257 

7.  Cartilaginous,  351 

8.  The  Fibro-Cartilaginous,  256 

9.  Muscular,      -  351 

10.  Erectile,  or  Spongy,  as  Penis,  &c.  II.  p.  85 

11.  Mucous,  50 

12.  Serous,  10 

13.  Dermoid,  or  Skin,  I.  p.  328 

14.  Glandular,  as  Liver,  Kidneys,  &c.  &c.  II.  p.  56 

The  distinctions  of  tissue  do  not  rest  upon  an  imagi- 
nary basis,  but  have  nature  for  their  foundation.  The 
organization  of  each  has  well  marked,  and  characteristic 

*  Bichat  admits  twenty-one  elementary  tissues,  but  several  of  them 
are  but  modifications  of  one  and  the  same.  For  example,  the  arterial, 
the  venous,  and  the  absorbent,  belong  all  to  the  vascular,  and  I  have 
thought  it  useful  to  concentrate  them  under  one  head;  and  so  of  some 
others,  where  the  analogy  is  equally  evident.  As  the  nature  of  the 
work  did  not  admit  of  the  consecutive  description  of  these  tissues,  re- 
ference is  made  to  the  pages  in  which  they  are  discussed.  With  this 
guide  they  may  be  studied  in  immediate  succession,  by  the  person 
desirous  of  an  outline  of  General  Anatomy. 


INTRODUCTION.  XXI 

peculiarities,  which  may  be  ascertained  by  their  dis- 
eases, and  by  the  influence  of  different  agents,  as  heat, 
air,  water,  acids,  alkalis,  neutral  salts,  and  putrefaction. 
Each  tissue  has  its  particular  strength,  and  its  particular 
mode  of  sensibility,  upon  which  repose  all  its  vital  phe- 
nomena, and  the  blood  is  but  a  common  reservoir,  where 
each  chooses  what  is  in  relation  to  itself.  An  example, 
however,  will  serve  better  for  illustrating  these  several 
points.  The  stomach  is  composed  of  four  laminae,  one 
is  serous,  another  muscular,  a  third  cellular,  and  a  fourth 
mucous.  Each  of  these  laminse  has  its  appropriate  sen- 
sibilities and  mode  of  life,  which  may  cause  it  to  be  dis- 
eased, while  all  the  others  are  healthy.  Peritoneal  in- 
flammation may  invade  the  first,  the  cramps  of  colic  the 
second  or  muscular,  the  infiltration  of  dropsy  the  third 
or  cellular,  and  dyspepsia  the  fourth  or  mucous. 

It  thus  happens,  that  the  diversity  of  the  tissue  of  an 
affected  organ  modifies  the  symptoms  of  its  diseases,  and 
especially  their  duration.  Hence,  nothing  is  more  vague 
in  medicine,  in  regard  to  duration,  than  the  terms  chronic 
and  acute.  An  inflammation  in  one  tissue  will  go  na- 
turally through  its  stages  in  a  few  days,  as,  for  exam- 
ple, in  the  skin,  cellular  substance,  mucous  membranes; 
while  in  the  bones  and  ligaments,  on  a  natural  progress 
being  also  observed,  weeks  and  months  are  required  for 
its  accomplishment.  It  is  evident,  therefore,  that  a 
time  which  is  chronic  in  the  first  three  tissues,  is  acute 
in  the  lagt  two. 

A  chemical  analysis  of  the  body  demonstrates  only  a 
few  elementary  principles;  and  they  are  varied  in  their 
combinations  by  a  greater  or  less  proportion  of  one  or 
the  other.  Calcareous  matter,  the  neutral  salts,  carbon, 
hydrogen,  oxygen,  nitrogen,  sulphur,  iron,  wrought  up 
by  the  powers  of  animalization  into  gelatine,  albumen, 
and  fibrine,  which  again  are  elaborated  into  the  fibrous 
and  laminated  tissue,  constitute  about  the  sum  total  of 


XX11  INTRODUCTION. 

the  results  of  the  experiments  of  animal  chemistry.  It 
has  yet  to  find  out  the  laws  of  the  phenomena  which 
give  to  these  elementary  atoms  the  condition  of  blood, 
and  afterwards  change  this  blood  into  muscles,  nerves, 
and  other  things. 

The  whole  body  is  formed  of  solid  sand  of  fluids.  The 
former,  when  unravelled,  consist  of  fibres,  of  laminae, 
and  of  molecules;  their  mechanical  division  does  not  ad- 
mit of  any  greater  separation.  Many  of  the  laminae  are 
arranged  into  membranes,  thus  forming  hollow  viscera, 
for  containing  either  articles  of  food  or  the  excretions; 
others  surround  the  different  solid  viscera  and  separate 
them  from  the  contiguous  parts.  Other  laminae  pene- 
trate through  the  most  compact  structure,  and  indeed 
form  the  nidus  in  which  its  atoms  or  particles  are  de- 
posited. Many  of  these  laminae  consist  of  several  thin- 
ner laminae,  placed  together  and  united  by  filaments  ar- 
ranged into  cells,  which  cells  receive  the  ultimate  par- 
ticles of  the  whole  fabric,  and  constitute  its  base.  The 
lamhue  also,  by  being  wrought  into  cylinders,  constitute 
vessels  of  different  kinds,  which  are  distributed  in  such 
numbers  through  the  body,  that  by  far  the  greater  part 
of  its  structure  seems  to  be  formed  of  them.  In  regard 
to  the  fluids,  they  are  extremely  abundant  in  number 
and  in  quantity,  and  are  found  in  the  cells  of  the  lami- 
nated tissue,  and  in  the  several  vessels.  One  not  accus- 
tomed to  the  process^ would  be  astonished  to  see,  when 
these  fluids  evaporate  by  exposure  to  the  air,  that  near- 
ly all  parts  of  the  body,  except  the  skeleton,  lose  from 
one-half  to  two-thirds  of  their  original  bulk,  and  some 
parts  even  more.  The  several  solid  parts  of  the  body 
are  then  literally  kept  soaked  during  life  in  the  fluids ; 
which  have  for  a  principal  constituent,  simply  water. 

There  are  some  animals  whose  organization  is  so  sim- 
ple that  they  possess  only  the  power  of  sensation;  and 
of  motion  in  one  part  upon  another.  This  is  perhaps 


INTRODUCTION.  XXiii 

the  lowest  degree  in  which,  animal  life  does  exist,  or 
possibly  can  exist,  without  a  new  order  of  things. 
These  qualities,  sensation  and  motion,  are  of  necessity 
combined  always;  they  constitute  the  first  ingredients 
in  the  composition  of  life,  both  in  vegetables  and  ani- 
mals, and  by  being  modified  in  various  ways  by  their 
application  to  different  organs,  may  be  traced  up  to  the 
perfect  animal,  man. 

Nutrition  is  the  first  want  of  every  being,  and  is  one 
of  the  modes  of  sensation;  therefore,  before  any  other  ap- 
paratus is  provided  for  animal  life,  means  are  resorted  to 
to  carry  it  on.     Vegetables  are  fixed  to  the  soil,  and  are 
furnished  with  great  numbers  of  porous  roots,  which  by 
spreading  in  different  directions,  come  in  contact  with 
the  moisture  of  the  ground  and  by  simple  absorption 
conduct  it  as  the  aliment  of  the  plant.  There  are  many 
animals  which  have  a  vegetative  life  almost  as  simple 
as  this,  are  fixed  permanently  to  the  spot  where  they 
came  into  existence;  others  are  permitted  to  change 
their  places  of  abode,  and  a  provision  for  nourishment 
by  roots  would  not  answer;  hence  comes  the  necessity 
of  a  stomach,  or  reservoir  in  the  interior  of  the  body, 
into  which  aliment  may  be  introduced,  and  transported 
along  with  the  animal.  In  many  instances  this  stomach 
seems  to  constitute  the  whole  animal,  as  in  a  hydatid : 
it  receives  such  simple  fluids  as  compose  the  medium  in 
which  it  resides,  and  carries  on  its  digestion,  with  so 
little  change  of  the  alimentary  matter,  that  there  seems 
to  be  nothing  of  an  excrernentitious  kind,  as  commonly 
understood,  thrown  off.  These  animals  are  found  abun- 
dantly in  the  waters  of  tropical  regions,  exist  sometimes 
in  the  brain  of  man,  and  of  sheep,  in  the  uterus,  and  in 
almost  every  part  of  the  body.     But,  again,  there  are 
stomachs  of  a  more  complex  kind,  which  have  opening 
into  them  a  great  number  of  absorbing  orifices,  called, 
in  the  striking  language  of  Boerhaave,  "  genuine  inter- 


XXIV  INTRODUCTION. 

nal  roots."  These  stomachs  may  admit  fluids  only,  or 
they  may  be  large  enough  to  receive  considerable  mass- 
es of  solid  aliment.  In  the  latter  case  exists  the  neces- 
sity of  teeth,  or  some  mechanical  means  of  triturating 
the  solid  food  into  such  fine  pieces,  as  will  admit  of  its 
being  exposed  by  an  extensive  surface  to  the  action  of 
the  stomach.  But  as  much  of  the  matter  thus  carried 
in  is  unfit  for  assimilation,  and  there  may  be  even  more 
of  it  than  is  required,  an  intestinal  canal  is  provided, 
by  which  it  is  carried  oat  again.  Here  then  commence 
the  phenomena  of  a  true  digestion,  with  all  its  modifi- 
cations and  stages. 

The  very  simple  structure  of  a  plant,  and  its  perma- 
nent locality  is  attended  with  a  circulation  of  its  juices 
equally  simple ;  which  is  performed  and  maintained  by 
the  capillary  attraction  of  its  pores,  and  by  evaporation 
from  its  higher  and  more  exposed  parts.  This  circulation 
is  the  more  rapid  as  the  evaporation  becomes  greater : 
but  the  latter  may  become  changed  into  absorption  by 
the  humidity  of  the  atmosphere ;  and  the  circulation  be  as 
a  consequence  reversed  from  the  branches  to  the  roots. 
But  it  is  evident  that  such  animals  as  possess  extensively 
the  powers  of  locomotion,  besides  having  organs  more 
numerous  and  more  complex  than  the  parallel  fibrillse  of 
vegetables,  will  frequently  find  themselves  in  such  con- 
ditions of  temperature  and  locality,  that  a  similar  circu- 
lation of  the  nutritious  fiuid  in  them  could  not  be  main- 
tained. Hence  it  is  necessary  to  have  more  powerful 
and  regular  agents  for  carrying  on  the  circulation. 
They,  therefore,  are  furnished  with  innumerable  blood 
vessels,  called  arteries  and  veins,  which  have  a  common 
centre,  the  heart,  for  propelling  through  them  the  blood 
or  nutritive  fluid  to  all  parts  of  the  system.  From  the 
heart  being  furnished  with  valves,  which  are  all  in  one 
direction,  the  blood  can  flow  only  in  a  corresponding 
course;  thus  it  is  forced  by  the  heart  into  the  arteries, 


INTRODUCTION.  XXV 

and  after  moistening  the  most  minute  fibres  it  is  received 
into  the  capillary  extremities  of  the  veins  and  brought 
back  to  the  heart,  where  it  receives  another  impulse,  and 
performs  again  the  round  of  the  body,  and  so  on  in  suc- 
cession. This  phenomenon  is  called  the  circulation. 
When  it  exists  in  animals,  blood  is  always  to  be  found; 
for  the  most  part  red,  but  in  many  species  white  or  trans- 
parent. The  use  of  the  blood  in  them  is  to  receive  from 
the  alimentary  canal,  from  the  skin  and  lungs,  such 
matter  as  has  been  assimilated,  and  to  convey  it  to  eve- 
ry part  of  the  body,  for  the  purpose  of  repairing  its 
waste,  or  providing  for  its  growth.  It  is  at  the  very 
extremities  of  the  arteries  that  this  deposite  occurs,  and 
the  blood  getting  into  the  veins  loses  its  bright  vermi- 
lion colour,  becomes  of  a  modena  or  dark  blue,  and  is 
no  longer  fit  for  the  purposes  of  life  till  some  of  the  prin- 
ciples which  it  has  lost  by  this  passage  are  restored  to 
it.  This  restoration  takes  place  in  the  lungs>  where  a 
sort  of  combustion  is  performed  by^  the  absorption  of 
oxygen,  This  process  is  called  respiration,  and  it  ex- 
ists in  all  things  that  live,  under  various  modifications 
of  the  apparatus  performing  it.  In  man  it  is  performed 
in  two  cellular  air  bags,  which  have  a  heart  indepen- 
dent of  the  one  just  mentioned,  for  propelling  the  blood 
through  the  ramifications  of  their  vessels.  In  fish  there 
are  gills,  which  have  their  surfaces  exposed  to  the  wa- 
ter, and  are  aerated  by  the  air  contained  in  the  water, 
and  the  same  heart  which  supplies  the  general  circu- 
lation, also  fills  a  large  artery,  that  is  distributed  very 
minutely  through  the  gills.  But  in  insects,  where 
there  are  no  blood  vessels,  and  the  nutritious  fluid  is 
contained  in  cells,  there  are,  distributed  over  their  bo- 
dies, air  tubes,  which  transmit  atmospheric  influence. 

The  blood  vessels,  iu  addition  to  the  function  of  car- 
rying nutritious  matter,  perform  an  essential  part  of  a 
very  different  character.  All  the  atoms  of  which  the 

VoL.L— 3 


XXVI  INTRODUCTION. 

body  is  composed,  after  residing  in  it  for  a  time,  be- 
come no  longer  fit  for  use;  their  farther  residence  is,  in 
fact,  injurious,  and  it  is  necessary  to  remove  them.  A 
system  of  vessels  is  provided  for  this  purpose,  called 
the  absorbents,  which  are  the  scavengers  of  the  body. 
Taking  up,  therefore,  these  eifete  atoms,  they  convey 
them  into  the  blood  vessels,  where  they  are  mixed  with 
the  common  mass  of  blood.  Several  organs  are  pro- 
vided, as  the  liver,  the  kidneys,  the  surface  of  the  body, 
and  the  lungs,  through  which  these  effete  particles  are 
discharged  from  the  blood  in  the  form  of  excretions; 
as  the  bile,  the  urine,  perspiration,  and  pulmonary  ex- 
halation. 

We  have  now  sketched  the  human  machine  as  far  as 
its  internal  existence,  or  self-preservation,  is  concerned 
in  the  functions  of  digestion,  circulation,  respiration, 
and  excretion.  Let  us  proceed  in  the  inquiry  by  a 
rapid  glance  at  those  organs  by  which  it  is  put  into  a 
relation  with  surrounding  objects,  and  on  which  it  de- 
pends for  the  sublime  operations  of  the  understanding. 

Sensation  is  derived  from  the  nervous  system,  com- 
posed of  the  brain,  the  spinal  marrow  and  the  nerves. 
The  latter  may  be  traced  to  many  parts  of  the  body, 
and  are  supposed  to  be  distributed  to  all.  They  main- 
tain its  different  sympathies,  keep  the  several  organs 
in  one  harmonious  course  of  action,  and,  in  some  in- 
stances at  least,  are  indispensable  to  the  performance 
of  their  functions.  In  addition  to  these,  many  of  the 
nerves  have  at  their  extremities  organs  of  a  particular 
construction,  each  fashioned  in  the  best  manner  for  the 
performance  of  its  functions,  in  making  us  acquainted 
with  exterior  objects.  The  interior  extremities  of  all 
these  nerves  terminate  either  in  the  brain  or  spinal 
marrow ;  the  external  are  the  points  intended  by  nature 
to  be  affected  by  the  objects  around  us;  but  it  is  indis- 
pensable to  consciousness,  that  their  line  of  communi- 


INTRODUCTION.  XXvii 

» 

cation  with  the  brain  be  not  interrupted.  The  sense 
most  extended  is  that  of  the  touch,  which  is  enjoyed 
by  all  parts  of  the  surface  of  the  body ;  the  others  are 
thought,  by  very  respectable  physiologists,  to  be  only 
more  exalted  modifications  of  it,  and  are  susceptible  of 
more  delicate  impressions.  It  is  scarcely  necessary  to 
mention  that  the  other  sensations  are  executed  by  the 
eye,  the  ear,  the  tongue,  and  the  nose. 

The  Sense  of  Touch  is  the  most  important  of  all,  and 
the  least  liable  to  error  in  its  reports.  To  exercise  it, 
it  is  necessary  for  the  body,  under  examination,  to  come 
into  contact  with  ours:  hence,  its  operations  are  so  me- 
chanical, that  but  little  is  left  to  the  imagination,  and 
they,  therefore,  serve  to  verify  and  to  correct  the  im- 
pressions on  the  other  senses,  more  particularly  those 
on  the  eye.  It  is  the  sense  of  touch  by  which  we  learn 
accurately  the  dimensions  of  bodies,  and  the  figures  of 
such  as  are  hard.  The  hand,  or  any  other  part,  by  be- 
ing applied  to  them  in  various  directions,  informs  us 
whether  they  are  flat,  round  or  angular.  A  greater  or 
less  degree  of  pressure  informs  us  whether  they  are 
soft  or  hard,  and  by  rubbing,  we  ascertain  whether 
they  are  rough  or  polished.  The  resistance  they  make 
to  motion,  teaches  us  whether  they  can  or  cannot  be 
moved,  and  their  being  impelled  against  us  shows  the 
momentum  with  which  they  act,  as  well  as  its  direc- 
tion. Our  ideas  of  heat  and  of  cold  are  also  derived 
from  this  source.  It  is  not  asserted  that  all  parts  of 
the  surface  of  the  body  enjoy  equally  the  sense  of  touch ; 
on  the  contrary,  this  sensibility  is  more  or  less  active, 
according  to  the  organization  of  the  part,  and  as  its 
nerves  are  more  or  less  numerous  and  exposed ;  hence 
we  find  it  most  exquisite  and  perfect  in  the  ends  of 
the  fingers.  This,  therefore,  being  the  most  import- 
ant of  the  senses,  the  magnitude  of  its  influence  on 


the  habits  and  intelligence  of  different  animals  is  im- 


Man,  from  the  nudity  and  the  delicacy  of  the  tex- 
ture of  his  skin,  derives*  from  this  source,  a  discrimi- 
nation and  refinement*  in_  regaid  to  the  natme  of 
bodies,  much  superior  to  what  many  other 


The  Sight  enables  us  to  distinguish 
quantity,  and  the  direction  of  the  rays  .of  light  which 
proceed  from  a  luminous  body;  or,  in  other  words,  to 

ever,  of  the  latter  we  are  exposed  to  great  deception; 
lor  the  lays  of  light,  by  Mling  on  a-  minor,  or  any 
other  plane  reflecting  .surface*  before  they  reach  the 
eye,  will  induce  us  to  believe  the  body  to  be  in  that 
direction.  Bodies  which  are  near,  reflect  more  rays 
of  light  than  such  as  are  distant:  we  thus  estimate  dis- 
tance by  the  eye;  but  it  happens  continually,  that 
some  bodies  naturally  reflect  more  rays  than  others; 
in  consequence  of  which  a  rery  luminous  body,  at  a 
great  distance,  wffl  frequently  be  thought  to  be  much 
nearer  to  us,  than  such  as  are  more  within  our  reach. 
Mistakes  of  this  kind  can  only  be  corrected  by  the 
sense  of  touch,  and  our  habitual  reference  to  it,  and 

us  to  fora 


•tens  the  touch  in  die  rapidity  with  which  it 

in  the  extensiveness  of  its  ap- 
in  a  single  moment.  It  is*  therefore*  an  oigan 
of  the  first  utility  in  1l*3>fc™g  us  acquainted  with  s«p- 
lounding  objects.  Man  does  not  possess  it  to  that 

ther  see  as  far  as  the  Tuhure  or  eagle,  nor  so  minutely 
as  die  fly;  yet  his  ingenuity  has  t  u»iifc.d  him  to 
both.    Fur,withthetefaH»pe,he 


INTRODUCTION. 

the  immensitity  of  space,  which,  under  common  < 
munition,  are  either  invisible,  or  form  mere  points  in 
the  heavens.     And  with  the  microscope  he  sees  the 
texture  of  the  most  minute  atom. 

The  Ear,  along  with  the  powers  of  articulation,  ena- 
bles the  whole  human  family  to  make  a  common  stock 
of  the  knowledge  which  each  individual  may  possess. 
As  connected  with  the  preservation  of  the  individual, 
it  is  much  less  important  than  the  eye  or  the  touch; 
yet,  considering  it  as  a  means  by  which  we  receive 
knowledge  and  impart  it  to  others,  the  aggregate  of 
human  intellect  depends  for  its  present  state  and  future 
improvement,  essentially  upon  it.  In  its  acuteness, 
we  are  much  inferior  to  many  other  animals;  neither 
have  we,  by  instruments,  been  able  to  do  much  in  im- 
proving it :  yet,  by  cultivation  and  by  studying  its  most 
minute  and  delicate  impressions,  an  endless  source  of 
instruction  and  amusement  has  been  opened  to  us,  in 
the  intonations  of  language,  and  in  the  enrapturing 
strains  of  harmony.  It  eminently  qualifies  man  for 
the  social  state,  occasionally  warns  him  of  danger,  and 
allures  him  to  such  things  as  are  useful  to  his  sub- 
sistence. 

In  regard  to  the  Taste  and  to  the  Smell,  they  make 
us  acquainted  only  with  such  objects  as  are  necessary 
to  our  subsistence.  They  are  enjoyed  too  imperfectly 
by  man,  for  them  to  become  a  fruitful  source  of  his 
intelligence.  As  they  principally  lead  us  to  filling  the 
stomach,  and  to  debasing  the  intellectual  man  into  the 
beast,  that  eats  and  dies;  the  wisdom  of  nature  is  as 
fully  demonstrated  in  the  imperfection  which  she  has 
put  upon  these  senses,  and  our  inability  to  improve 
them,  as  in  the  exalted  and  varied  degrees  to  which 

3* 


XXX  INTRODUCTION. 

she  has  carried  the  others.  The  keenness  of  the  scent 
of  the  hound,  and  the  discriminating  nicety  of  the  bee, 
in  opening  sources  of  enjoyment  merely  physical, 
would  have  degraded,  instead  of  elevating  us;  by  en- 
grossing our  time  and  ingenuity,  in  the  development 
of  pleasures  incompatible  with  our  constitutions  and 
destinies. 

Man  being  thus  constituted,  it  is  worthy  of  inquiry 
in  what  his  life  consists.  According  to  the  celebrated 
Bichat,  it  is  "  the  aggregate  of  those  functions  by 
which  death  is  resisted.  For  such,  indeed,  is  the  con- 
dition on  which  we  live,  that  every  thing  surrounding 
us  has  a  tendency  to  produce  our  dissolution,  by  the 
affinities  existing  between  their  atoms,  and  the  atoms 
of  which  a  living  body  is  composed.  It  is  plain,  there- 
fore, that  the  principle  of  life,  like  all  other  principles 
in  nature,  incomprehensible  in  itself,  must  be-  studied 
by  its  phenomena."* 

There  are  two  remarkable  modifications  of  life :  one 
is  common  to  the  vegetable  and  to  the  animal,  the  other 
is  the  exclusive  attribute  of  the  latter.  Under  the  first 
modification,  are  included  assimilation  and  excretion, 
which,  though  exercised  under  apparently  different 
circumstances  in  animals  and  in  plants,  are  probably 
essentially  the  same  in  both.  This  modification  is 
termed  by  Bichat,  Organic  Life.  By  the  second  mo- 
dification of  life,  the  animal  has  a  more  extended 
sphere  of  existence  than  the  vegetable,  is  put  into  a 
certain  relation  with  all  the  objects  that  surround  him, 
is  made  the  inhabitant  of  the  whole  world,  and  not, 
like  the  vegetable,  confined  for  ever  to  the  place  of  its 
birth.  By  it  the  animal  feels,  and  is  conscious  of  ex- 
ternal objects,  reflects  upon  them,  moves  voluntarily,. 

*•  Recherches  sur  la  vie  et  La  Mort. 


or  r 


•or  J 

V^ 
INTRODUCTION.  XXXI 

and  can  communicate,  by  the  voice,  his  wants  and  ap- 
prehensions, his  pleasures  and  his  pains.  The  func- 
tions included  under  the  second  modification,  are 
termed,  by  Bichat,  Animal  Life. 

Each  of  these  lives  has  two  orders  of  functions,  keep- 
ing up  its  connexion  with  the  objects  destined  for  its 
existence.  In  animal  life,  one  of  these  orders  may  be 
said  to  commence  at  the  surface  of  the  body,  and  to  be 
extended  towards  the  centre,  the  impression  of  exterior 
objects  affecting-  first  the  senses,  then  the  trunks  of 
nerves,  and  lastly,  the  brain.  A  second  movement, 
constituting  the  second  order  of  functions,  is  afterwards 
made  from  the  centre  to  the  circumference,  by  which 
the  influence  of  the  brain  is  exercised  on  the  organs  of 
locomotion  and  of  voice.  These  two  functions,  in  ani- 
mal life,  are  perfectly  equivalent  in  their  operations. 
He  who  feels  the  most,  will  also  act  the  most.  Early 
life  is  the  period  of  quick  and  multiplied  sensations,  so 
is  it  the  period  of  quick  and  multiplied  movements. 
A  partial,  or  a  total  privation  of  the  sense  of  sight,. 
causes  us  to  move  cautiously  and  slowly  onwards. 
The  suspension  of  our  communicatiori,  through  sleep, 
with  exterior  objects,  causes  also  a  suspension  of  the 
faculties  of  locomotion  and  of  voice..  In  organic  life,, 
the  first  order  of  functions  assimilates  to  the  animal 
the  substances  which  must  nourish  him,  and  includes 
digestion,  circulation,  respiration,  and  nutrition;  under 
the  influence  of  which  four  functions,  every  thing  must 
pass  before  it  can  be  assimilated.  But,  after  a  temporary 
residence,  the  assimilated  particles  becoming  effete  and 
noxious,  have  to  be  carried  away  out  of  the  body  :  by 
which  means  the  second  order  of  functions  in  organic 
life  is  established,  consisting  of  absorption,  circulation, 
exhalation,  and  secretion. 

The  two  functions  of  organic  life  differ,  however, 
from  those  of  animal  life,  in  not  observing,  on  all  occa- 


XXX11  INTRODUCTION. 

sions,  an  equivalence  of  action :  the  diminution  of  assi- 
milation does  not  involve  a  corresponding  diminution 
in  excretion ;  hence,  follow  emaciation  and  marasmus, 
conditions  in  which,  assimilation  ceasing  in  part,  dis- 
assimilation  is  exercised  to  the  usual  extent,  or  near  it. 
From  this  sketch,  it  is  seen  that  the  circulation  of  the 
blood  is  the  connecting  link  of  the  two  orders  of  func- 
tions in  organic  life,  as  the  brain  is  the  connecting  link 
of  the  two  orders  of  functions  in  animal  life.  The  blood 
is,  therefore,  in  fact,  composed  of  two  parts  or  descrip- 
tions of  matter :  one  is  recrementitial,  derived  from  the 
aliment,  and  subservient  to  the  renovation  and  growth 
of  parts ;  the  other  is  excrementitial,  derived  from  the 
wrecks  of  all  our  organs,  and  under  the  necessity  of 
being  cast  away  as  useless. 

M.  Bichat  thinks  the  division  of  life  into  animal  and 
organic,  fully  warranted  by  their .  differing  much  from 
each  other  in  the  exterior  shape  of  their  respective  or- 
gans,— in  their  mode  of  action, — in  the  duration  of  their 
action, — in  the  effects  of  custom  or  habit  on  them, — in 
their  relation  to  the  moral  part  of  man,  and  in  their  vi- 
tal force. 

One  of  the  most  prominent  differences  in  the  two 
lives,  is  the  symmetry  and  duplicity  of  the  Organs  of 
Animal  Life,  and  the  irregularity  in  shape  of  those  be- 
longing to  Organic  Life.  The  impression  of  Light  is 
received  by  two  organs  exactly  alike.  Hearing — 
Smelling — Touching — are  likewise  performed  by  or- 
gans having  their  congeners  on  the  opposite  sides  of  the 
body;  and  even  Tasting,  though  apparently  performed 
by  one  organ,  has  that  organ  divided  into  two  equal 
and  symmetrical  parts,  thus  making  it  like  the  other 
organs.  The  whole  exterior  surface  of  the  body  is,  in- 
deed, manifestly  divided  into  two  equal  parts,  marked 
off  from  each  other  by  the  fissure  in  the  nose,  the  upper 
lip,  the  chin,  the  raphe  of  the  scrotum  and  perineum,. 


INTRODUCTION.  XXX111 

the  spinous  processes,  and  the  depression  in  the  supe- 
rior posterior  part  of  the  neck.  The  Brain  and  Spinal 
Marrow,  as  belonging  to  animal  life,  consist  of  two 
halves,  presenting  corresponding  arrangements  in  the 
development  of  cavities  and  prominences,  and  so  on, 
and  in  sending  similar  nerves  to  the  organs  of  locomo- 
tion and  of  voice. 

The  organs  of  organic  life  are  marked,  on  the  contra- 
ry, by  the  character  of  striking  dissimilitude  in  their 
two  halves,  as  manifested  in  the  liver,  the  spleen,  the 
stomach,  the  intestines,  the  heart,  and  the  great  vessels 
belonging  to  it.  There  are,  however,  some  organs  of 
organic  life  in  which  the  difference  is  less  prominent, 
as  the  lungs  of  the  two  sides,  the  pulmonary  arteries, 
the  veins,  the  trachea,  the  kidneys,  the  capsulse  renales, 
and  the  salivary  glands. 

From  what  has  been  said,  we  are,  perhaps,  prepared 
to  admit  with  M.  Bichat,  that  animal  life  is  double;  that 
its  phenomena  being  executed  after  the  same  manner  on 
both  sides  of  the  body,  it  is  very  possible  for  the  actions 
of  one  side  to  be  suspended  or  destroyed  while  those  of 
the  other  go  on.  This,  in  fact,  happens  in  certain  pal- 
sies, where  the  sensibility  and  motion  of  one  side  are  so 
completely  suspended,  that  it  resembles  a  vegetable;  all 
relation  with  exterior  objects  being  cut  off,  and  nothing 
but  the  function  of  nutrition  being  preserved ;  whereas 
the  other  side  retains  all  its  animal  properties.  For 
these  reasons  Bichat  has  very  quaintly  observed  that  we 
have  a  right  life  and  a  left  life.  In  organic  life,  on  the 
contrary,  the  functions  of  the  two  halves  of  any  organ 
are  so  allied,  that  the  lesion  of  one  affects  the  other. 
The  liver,  in  a  disease  on  one  side,  has  its  functions  im- 
paired throughout :  it  is  the  same  with  the  intestinal  ca- 
nal, and  with  the  heart. 

Congenital  deformities  are  said  to  be  more  frequent  in 
the  organs  of  organic  life  than  in  those  of  animal  life. 


XXXIV  INTRODUCTION.          * 

Several  cases  have  occurred,  and  Bichat  relates  one 
which  happened  in  his  own  amphitheatre,  where  there 
was  a  general  displacement  of  the  digestive,  the  circu- 
latory, the  respiratory,  and  the  secretory  viscera.  The 
stomach,  the  spleen,  the  sigmoid  flexure  of  the  colon, 
the  point  of  the  heart,  the  aorta,  and  the  lung  with  two 
lobes,  were  all  on  the  right  side.  But  the  liver,  the 
coecum,  the  base  of  the  heart,  the  vense  cavse,  the  vena 
azygos,  and  the  lung  with  three  lobes  were  on  the  left 
side.  All  the  organs  placed  beneath  the  middle  line, 
as  the  mediastinum,  the  mesentery,  the  duodenum,  the 
pancreas,  the  division  of  the  trachea,  were  reversed. 
Latterly  I  have  had  occasion  to  observe,  in  our  own 
dissecting  rooms,  two  cases  of  the  caput  coli  removed 
from  the  ri^ht  iliac  into  the  left  iliac  region;  the  colon 

O  O  * 

\vas  of  the  common  size  and  length,  and  being  confined 
to  the  left  side  of  the  abdomen,  formed  there  a  loop, 
which  ascended  into  the  left  hypochondriac  region,  and 
then  descended  as  usual.  In  these  cases,  as  there  was 
no  transverse  mesocolon,  the  duodenum  had  all  the 
coats  of  the  other  intestines;  and  was  not  attached  to 
the  front  of  the  right  kidney  and  to  the  spine.  One  of 
these  was  an  adult  female  subject  of  considerable  cor- 
pulency, the  other  a  corpulent  male. 

Another  difference  between  organic  and  animal  life 
exists  in  the  mode  of  action  of  their  respective  organs. 
Each  of  the  organs  of  animal  life  being  double,  our  sen- 
sations are  the  more  exact,  as  there  exists  between  the 
two  impressions,  from  which  they  result,  a  more  perfect 
correspondence.  We  see  badly  when  the  images  trans- 
mitted to  the  brain  are  derived  through  eyes  of  unequal 
strength.  Without  knowing  this  law  as  theorists,  we 
instinctively  show  its  influence  in  shutting  one  eye 
while  looking  through  a  convex  glass;  whereby  we  pre- 
vent a  confusion  of  images  arising  from  two  impres- 
sions of  unequal  force,  concerning  the  same  body :  when 


INTRODUCTION.  XXXV 

one  eye  is  weaker  than  the  other,  we  squint  involun- 
tarily, and  it  finally  becomes  a  habit,  in  order  to  avoid 
the  confusion  of  perception  from  two  unequal  images 
on  the  brain.  This  accounts  for  squinting,  both  in  early 
life,  from  some  congenital  cause,  and  for  that  squinting 
which  is  the  result  of  inflammation,  in  more  advanced 
life.  A  little  reflection  on  this  head  will  satisfy  us;  for 
as  a  single  judgment  or  perception  is,  for  the  most  part, 
formed  from  the  two  impressions,  one  on  each  eye,  how 
is  it  possible  that  this  judgment  can  be  accurate,  when 
the  same  body  is  presented  at  the  same  moment  with 
vivid  or  faint  colours,  accordingly  as  it  was  painted  on 
the  strong  or  weak  eye? 

The  Ear  is  subjected  to  the  same  law  as  the  eye.  If, 
in  the  two  sensations  composing  the  act  of  hearing,  one 
is  received  upon  an  organ  better  developed  than  the 
other,  and  more  discriminating  in  its  functions,  it  will 
leave  an  impression  more  clear  and  distinct;  but  the 
brain  being  affected  simultaneously  by  the  unequal  im- 
pressions, will  be  the  seat  of  an  imperfect  conception. 
This  case  constitutes  a  false  ear  in  music,  and  from  the 
impressions  being  continually  confused,  prevents  the 
individual  from  judging  rightly  between  harmony  and 
dissonance. 

A  similar  reasoning  has  been  founded  by  Bichat  upon 
the  structure  of  the  Nose,  Mouth,  and  Organs  of  Touch. 
He  believes  also  that  the  brain  itself,  as  the  seat  of  the 
mind,  may  become  the  cause  of  error  in  our  ideas,  when 
the  two  halves  of  it  are  not  perfectly  alike;  for  example, 
if  one  of  the  hemispheres  be  more  strongly  organized 
than  the  other,  better  developed  every  where,  and  more 
susceptible  of  a  vivid  impression.  The  brain  transmits 
to  the  soul  the  impression  or  impulse  derived  from  the 
senses,  as  the  latter  transmit  to  the  brain  their  impres- 
sions; it  is,  therefore,  to  be  believed  that  the  soul  will 
perceive  confusedly,  when  the  hemispheres,  being  une- 


XXXVI  INTRODUCTION. 

qual  in  force,  do  not  blend  into  one,  the  double  impres- 
sion upon  them.  In  proof  of  this,  it  is  common  to  see 
mental  derangements  depending  on  the  compression  of 
-a  hemisphere  by  effused  blood,  by  pus,  by  depressed 
bone,  and  by  an  exostosis  from  the  internal  face  of  the 
cranium.  Even  where  every  sign  of  compression  is 
removed,  the  hemisphere  occasionally  takes  a  long  time 
to  regain  its  action,  so  as  to  recover  from  the  alienation. 

This  harmony  of  action  exists  also  in  the  organs  of 
locomotion,  and  of  voice;  and  any  thing  which  inter- 
rupts their  symmetry  destroys  the  precision  with  which 
their  functions  are  executed. 

Opposed  to  this  harmony  in  the  shape  and  functions 
of  the  organs  of  animal  life,  the  most  striking  differ- 
ences may  take  •  place  between  the  organs  of  organic 
life,  without  much  disturbance  in  the  general  result. 
For  example,  in  disparities  of  the  kidneys,  of  the  lungs, 
of  the  salivary  glands,  &c.,  their  functions  are  not,  by 
any  means,  the  less  perfectly  performed.  The  circu- 
lation remains  the  same  in  the  midst  of  the  frequent 
varieties  of  the  vascular  system  on  the  two  sides  of  the 
body,  whether  those  varieties  exist  naturally,  or  whe- 
ther they  depend  upon  artificial  obliterations  of  the 
large  vessels,  as  in  aneurism. 

Another  very  striking  difference  in  the  two  lives  may 
be  observed  in  the  duration  of  their  action.  All  the  ex- 
cretions proceed  uninterruptedly,  though  not  uniformly. 
Exhalation  and  absorption  succeed  each  other  incessant- 
ly; assimilation  and  dissimilation  follow  the  same  rule. 
On  the  other  hand,  every  organ  of  animal  life,  in  the  ex- 
ercise of  its  functions,  has  alterations  of  activity  and  of 
complete  repose.  The  senses,  fatigued  by  long  appli- 
cation, are,  for  the  time,  disqualified  from  farther  action. 
— The  Ear  is  no  longer  sensible  of  sounds : — The  Eye 
is  closed  to  Light ; — Sapid  bodies  no  longer  excite  the 


INTRODUCTION.  XXXV11 

Tongue ; — The  Nose  is  insensible  to  odours ; — And  the 
Touch  becomes  obtuse.  Fatigued  by  the  continued  ex- 
ercise of  perception,  of  imagination,  and  of  memory, 
the  brain  has  to  recruit  its  strength,  by  a  state  of  com- 
plete inactivity  for  some  time.     The  muscles,  relaxed 
by  fatigue,  are  incapable  of  farther  contraction,  till  they 
have  been  permitted  to  rest;  hence  the  necessary  inter- 
mission, in  every  individual,  of  locomotion  and  of  voice. 
This  intermission  of  action  is  sometimes  extended  to 
all  the  organs  of  animal  life  at  the  same  time ;  on  other 
occasions,  only  a  part  of  them  is  affected  by  it.     It  is 
in  this  way  that  the  brain  frequently  continues  in  the 
active  exercise  of  thought,  while  the  senses,  as  well  as 
the  powers  of  locomotion  and  of  voice  are  suspended. 

In  addition  to  the  foregoing  views,  it  has  also  been 
•suggested  by  Bichat,  that  another  striking  difference 
between  organic  and  animal  life,  is  found  in  the  epoch 
and  mode  of  their  origin.     Organic  life  exists  from  the 
first  moments  of  conception ;  but  animal  life  does  not 
commence  till  after  birth,  when  exterior  objects  are  es- 
tablished in  a  certain  relation  with  the  individual.     It 
is  more  than  probable,  that  the  function  of  the  Eye,  the 
Ear,  the  Tongue,  and  the  Nose,  does  not  exist  in  such 
manner  as  to  communicate  their  several  sensations  in 
the  foetus;  and  that  the  enjoyment  of  a  sort  of  indistinct 
sense  of  touch,  arising  from  its  striking  against  the  pa- 
rietes  of  the  womb,  is  the  only  circumstance  which  can 
give  the  latter  any  idea  of  its  existence;  it  is,  however, 
doubtful  whether  it  has  even  a  consciousness  on  that 
point.     The  organic  life,  on  the  contrary,  of  a  fetus, 
though  not  so  complicated  as  afterwards  is  still  re- 
markable for  the  promptitude  and  vigour  of  some  of  its 
functions,  particularly  of  assimilation;  and  in  a  very 
short  time  after  birth,  all  the  organs  which  it  employs 
reach  their  highest  degree  of  perfection,  and  thus  pre- 
VOL.  I.— 4 


XXXV111  INTRODUCTION. 

sent  a  very  different  case  from  the  organs  of  animal 
life. 

The  distinction  of  the  two  lives  is  farther  kept  up  in 
their  manner  of  ceasing  in  old  age.  Natural  death,  says 
Bichat,  is  remarkable,  in  terminating  animal  life  almost 
entirely,  a  long  time  before  it  does  organic  life.  The 
functions  of  the  first  cease  successively.  The  Sight  be- 
comes dim,  confused,  and  finally  is  extinguished.  The 
Ear  receives  the  impression  of  sounds  indistinctly,  then 
faintly,  and  afterwards  they  are  entirely  lost  upon  it. 
The  skin  becomes  shrivelled,  hardened,  loses  many  of 
its  vessels,  by  their  obliteration,  and  is  only  the  seat  of 
an  obscure  and  indistinct  touch;  the  hair  and  beard  be- 
come white,  and  fall  from  it.  The  Nose  loses  its  sen- 
sibility to  odours.  Of  all  the  senses,  it  has  been  often 
remarked,  that  the  Taste  remains  the  longest,  and  ex- 
hibits the  last  efforts  of  animal  life. 

The  powers  of  the  mind  disappear  along  with  those 
of  the  senses.   The  imagination  and  the  memory  are  ex- 
tinguished ;  the  latter,  however,  under  striking  circum- 
stances.    The  old  man  forgets,  in  an  instant,  what  was 
said  to  him,  because,  his  external  senses  being  weak- 
ened, do  not  confirm  sufficiently  the  impressions  on  his 
mind :  he  is,  however,  able  to  recollect  the  transactions  , 
of  early  life,  and  sometimes  retains  a  vivid  impression 
of  them.     He  differs  from  the  infant  in  this,  that  the 
latter  forms  his  judgments  from  what  is  passing,  where- 
as, the  former  forms  his  from  what  has  already  past. 
Both  are,  therefore,  liable  to  great  errors ;  for,  the  ac- 
curacy of  knowledge,  in  regard  to  things  present,  can 
only  be  obtained  by  comparing  them  with  other  things. 
Locomotion  and  voice  also  participate  in  the  decline  of 
the  other  organs  of  animal  life;  their  powers  are  intrin- 
sically weakened ;  besides  which,  a  certain  degree  of 
inactivity  is  imposed  on  them,  by  the  previous  decline 
of  the  brain  and  senses. 


INTRODUCTION.  XXXIX 

If  we  now  consider,  that  sleep  retrenches  about  one- 
third  of  the  whole  duration  of  animal  life ;  that  nine 
months  of  it  are  first  lost  in  gestation ;  and  that  the  ex- 
tinction of  our  senses  is  the  inheritance  of  old  age ;  it 
will  be  seen  how  great  is  the  difference  between,  the 
whole  duration  of  animal,  and  of  organic  life. 

It  has  been  remarked  by  Bichat,  that  the  idea  of  death 
is  painful  to  us  only  because  it  terminates  our  animal 
life,  or  those  functions  which  put  us  in  relation  with  sur- 
rounding objects.  This  is  the  privation  which  plants 
terror  and  dismay  on  the  borders  of  the  tomb.  It  is 
not  the  pain  of  death  that  we  fear,  for  many  dying  per- 
sons would  willingly  commute  death  for  an  uninter- 
rupted series  of  bodily  suffering.  But  if  it  were  possi- 
ble for  a  man  to  exist  whose  death  would  only  effect 
the  functions  of  organic  life,  as  the  circulation,  diges- 
tion, and  secretions,  allowing  the  exercise  of  the  senses 
and  the  mind  to  continue,  this  man  would  view  with 
indifference  the  extinction  of  organic  life,  because  he 
knows  that  the  happiness  of  living  is  not  attached  to  it,, 
and  that  he  would  remain  after  this  partial  death,  still 
in  a  condition  to  appreciate  all  the  delightful  ties  of  ex- 
istence. 


TABLE  OF  CONTENTS. 


VOLUME  I. 


BOOK  I.— SKELETON, 

Page 

PART  I. — General  Anatomy  of  Natural  Skeleton,  -      49 

CHAP.  I. — General  Anatomy  of  Bones,  •             50 

Sect.  1. — Number  and  Texture  of  Bones,  -      50 

2. — Composition  of  Bones,      -  -             56 

CHAP.  II. — Sect.  1.  Periosteum,       -             -             -  -63 

2.— Medulla,  65 

CHAP.  III. — Osteogeny,        -  -      67 

Sect  1. — Development  of  Bones,     -             -  -             67 

2.— Growth  of  Bones,        -  -      71 

3. — Formation  of  Callus,  -   ^       74 

PART  II. — Bones,  individually, 

CHAP.  I.— Trunk,  78 

Sect.  1. —Spine,  -      78 
2. — Development  of  Spine, 

3.— Uses  of  Spine,  •      90 

4. — Qssa  Innominata,  -             97 

5. — Pelvis,  generally,        -  -    102 

6. — Development  of  Pelvis,    -  105 

7.— Mechanism  of  Pelvis,              -  -    106 

8.— Thorax,  107 

9.— Cartilages  of  Ribs,      -  -    112 

10.— Development  of  Thorax,  -           115 

11.— Mechanism  of  Thorax,  •    116 

CHAP.  II.— Head,  121 

Sect.  1.— Cranium,        -  -    122 

2. — Individual  Bones  of  Cranium,       -  124 

3,— Face,  -    138 

4* 


Xlii  CONTENTS* 

Page 

CHAP.  III. — General  Considerations  on  Head,  -             -    149 

Sect.  1. — Sutures,  149 

2. — Diploic  Structure  of  Cranium,  -             -    156 

3. — Internal  Surface  of  Crsuiium,  •           158 

4. — External  Surface  of  Head,.      -  -    161 

&.— Nasal  Cavities,     -  -           165 

6.— Orbits  of  the  Eyes,     -  -    167 

7.— National  Peculiarities  of  Face,  -                         169 

8. — Development  of  Foetal  Head,  -             -    177 

CHAP.  IV.— Os  Hyoides,  181 

V. — Upper  Extremities,  -    182 

Sect.  1.— Shoulder,                           -,  182 

2.— Arm,  -    187 

3. — Fore  Arm,  189 

4. — Hand,  -    193 

5. — Development  of  Upper  Extremities,          •  201 

6. — Mechanism  of  Upper  Extremities,       -  -    202 

7. — Motions  of  Shoulder,  204 

8. — Motions  of  Shoulder  Joint,      -  -    205 

9. — Motions  of  Fore  Arm.       -..  207 

10 — Motions  of  Hand,        -  -    210 

CHAP.  VI. — Inferior  Extremities,  213 

Sect.  1. — Thigh  Bone,  -             -    213 

2.— Leg,         -            -             -  -                        217 

3.— Foot,  -    223 

4 — Development  of  Inferior  Extremities,  234 

5. — Standing,         -  ...    235 

6. — Locomotion,  241 

PART  III. — Articulations,        -  -             -    251 

CHAP.  I. — Cartilaginous  System,              ...  251, 

Accidental  Development  of  Cartilages,    -  -             -    253 

Perichondrium,        -                           -  .             .           254 

Articular  Cartilages,       -  .                  255 

CHAP.  II. — Fibro-Cartilaginous  System,  -.          256 

III. — Ligamentous  Tissue,        -  .             .    257 

Sect.  1.—    -  257 

2. — Ligaments  of  Joints,   -  .    260 

3  — Synovial  Articular  Capsules,  261 

CHAP.  IV. — Articulations  of  Lower  Jaw,       -  -             -    263 

V. — Ligaments  of  Spine,  .           266 

VI, — Ligaments  of  Pelvis,      -..  ._            --274 


CONTENTS.  Xliii 

Page 
CHAP.  VII. — Articulations  of  Thorax,     -  -  278 

VIII. — Articulations  of  Upper  Extremities,       -  -    283 

IX. — Articulations  of  Lower  Extremities,  -  299 


BOOK  II, 

PART  I.— Integuments  of  the  Body,   •-  -317 

CHAP.  I. — Cellular  Substance,     -  317 

II.— Adeps,     -  -    325 

PART  II. — Dermoid  Covering,      --  --         328 

CHAP.  I.— Of  the  Skin,  generally,     -  -    328 

SECT.  1. — Cutis  Vera,                                       -  330 

2. — Rete  Mucosum,  -    332 

3.._Cuticula,     -  336 

CHAP.  II. — Of  the  Sebaceous  Organs,  -             -    340 

HI.— Of  the  Nails,  342 

IV. — Of  the  Hairs,      -            --           -.  -            -    344 


BOOK  III. 

PART  I. — Muscles,                                     -.           -„  -          349 
CHAP.  I. — General  Anatomy  of  Muscles,       -  -    349 
II. — Muscular  Motion,       -             -             ...  -           355 
III. — Shape  of  Muscles,  -             _    359 
IV. — Tendons,        -  -           360 
PART   II. — Special  Anatomy  of  Muscles,        -  --            -    363 
CHAP.  I. — Muscles  of  Head  and  Neck,   --  363 
SECT.  1. — Muscles  of  Face,  ...            .    363 
2. — Muscles  of  Neck,  -  -           371 
CHAP.  II. — Muscles  of  Trunk,                        -  .             .    390 
SECT.  1. — Muscles  on  Front  of  Thorax,          -./  -           380 
2. — Muscles  and  Fasciae  of  Abdomen,  -             -    383 
3. — Muscles  of  Upper  and  Posterior  part  of  Abdo- 
men, ..   394 
4. — Muscles  on  Posterior  Face  of  Trunk,  -.          400 
CHAP.  III. — Of  the  Fasciae  and  Muscles  of  the  Upper  Extre- 
mities, -.                        -.           ..  .           4U 
SECT.  1.— Fascia,                                         ...  ..            -    411 
2. — Muscles  of  Shoulder,                        ..  ...         414 
3. — Muscles  of  Aim,                         -  ..            -416 
4. — Muscles  of  Fore  Arm,         ...  420 
§.-— Muscles  of  Hand,          -            -  -            .    439 


Xliv  CONTENTS. 

Page 

CHAP.  IV. — Of  the  Fascirc  and  Muscles  of  the  Lower  Extre- 
mities, -  -          436 
Sect.  1.— Fascia*  -    436 
2.— Muscles  of  Thigh,  442 
8. — Muscles  of  Leg,  -             -    452 
4.— Muscles  of  Foot,  -  460 

BOOK  IV. 

ORGANS  OF  DIGESTION,  •    467 

PART  I. — Organs  of  Mastication  and  Deglutition,  469 

CHAP.  I.— Mouth,     -  -    469 

II.— Teeth,                        - .  471 

Sect.  1. — Number  of  Teeth,  and  Subdivision,  -            -471 

2.— Of  the  Texture  and  Organization  of  the  Teeth,   474 

3.— Gums,  -    478 

4.— Formation  of  Teeth,  479 

5.— Dentition,       -  -    484 

6. — Irregularities  in  Dentition,             •'  490 

CHAP.  III.— Tongue,  -    493 

Sect.  1. — Muscles  of  Tongue,  493 

2. — Mucous  Covering  of  Tongue,  -    495 

CHAP.  IV.— Palate,  498 

V.— Glands  of  Mouth,  •    500 

Sect.  1. — Muciparous  Glands,          •  500 

2. — Salivary  Glands,  -    501 

CHAP.  VI. — Pharynx  and  (Esophagus,   -  504 

Sect.  1.— Pharynx,        -  -    504 

2.- — (Esophagus,  507. 


VOLUME   II. 


BOOK  IV. 

CONTINUES. 

Page 

PART  II. — Organs  of  Assimilation,       -  5 
CHAP.  I. — Abdomen,  generally,    -  5 
II. — Of  the  Peritoneum  and  Serous  Membranes,  gene- 
rally,      -  10 
Sect.  1. — Peritoneum,                                                 -  -    10 
2.— Omenta,  13 
3.— General  Anatomy  of  Serous  Membranes,  -    18 
€HAP.  III.— Chylopoietic  Viscera,  22 
Sect.  1.— Stomach,  -    22 
'2.— Intestinal  Canal,     -  28 
3. — Minute  Anatomy  of  the  Mucous  Coat  of  the 

Alimentary  Canal,  41 

4. — General  Anatomy  of  Mucous  Membranes,  -    50 

CHAP.  IV. — Assistant  Chylopoietic  Viscera,         -  56 

Sect.  1.— Liver,  -  -    56 

2. —Spleen,       -  64 

3.— Pancreas,         -             -             -             -  -    68 


BOOK  V. 

OF  THE  URINARY  ORGANS,  -  71 

BOOK  VI. 

ORGANS  OF  GENERATION,  -    85 

CHAP.  1. — Male  Organs  of  Generation,     -  -            -          85 

Sect.  1.— Penis,  -    85 

2. — Mucous  Glands  and  Apparatus,  -                       90 

3.— Testicles,  -    93 

4. — Muscles  and  Fasciae  of  Perineum,  -            •         100 


.  CONTENTS. 

Page 

CHAP.  II. — Female  Organs  of  Generation,  106 

Sect.  1.— Vulva,  -.    106 

2.— Vagina,    -.  110 

3. — Uterus,  audits  Appendages,  -                          -    112 

CHAP.  III.— Breasts,       -            -            -  -                       120 


BOOK  VII. 

ORGANS  OF  RESPIRATION,  •    125 

CHAP.  I. — Larynx,  ^            -           12fr 

II. — Of  the  Trachea  and  Glands  bordering  upon  it,       -    135 

Sect.  1.— Trachea,  135 

2.— Thyroid  Gland,  .             -    139 

3.  Thymus  Gland,       -,  141 

CHAP.  III.— Lunsrs,               -            -  -            «,           -    143 


BOOK  VIII. 

CIRCULATORY  SYSTEM,  153 
PART  I.— General  Anatomy  of  Circulatory  System,  -             -    153 
CHAP.  I. — General  Considerations,          -.  153- 
II.— Arteries/ -  -    16fr 
III.— Veins,  171 
IV.— Blood,    -  -    175 
Sect.  1.— Serum,     -  177 
2. — Coagulating  Lymph,  -  -    179 
3.— Red  Globules,       -  180. 
PART  II.— Special  Anatomy  of  Circulatory  System,  -             -    181 
CHAP.  I. — Heart,  181 
II.— Arteries,  -  -    195 
Sect.  1.— Of  the  Aorta  and  the  Branches  from  its  Cur- 
vature, -    195 
2. — The  Carotids  and  their  Branches,  198 
3. — Subclavian  and  Branches,  -    207 
4. — Branches  of  Descending  Thoracic  Aorta,  -  -         220 
5r.— Branches  of  Abdominal  Aorta,  -    222 
6. — Common  Iliacs,    -  230 
7.— Internal  Iliacs,  -    230 
8.— External  Iliacs,     -,  235 
CHAP.  III.— Of  the  Veins,     -  -    249 
$ect.  1.— Veins  of  Head  and  Neck,  249 
2. — Veins  of  Upper  Extremities,  -  -    258 


CONTENTS.  Xlvii 

Page 

Sect.  3 — Veins  of  Lower  Extremities,               -  261 

4. — Veins  of  Abdomen,  -           26$ 

5.— Vena  Portarum,  .    268 

CHAP.  IV. — Peculiarities  of  the  Circulatory  System  in  the 

Foetus,  -    270 

Sect.  1. — Peculiarities  of  Foetus,      -    .  271 

2. — Peculiarities  of  Circulation  of  Foetus,  -    275 

CHAP.  V. — General  Anatomy  of  Absorbent  System,  -           280 

VI. — Special  Anatomy  of  Absorbent  System,   -  -    289 

Sect.  1. — Absorbents  of  Head  and  Neck,     -  289 

2. — Absorbents  of  Upper  Extremities,       -  -    291 

3.— Absorbents  of  Inferior  Extremities,  293 

4. — Deep  Absorbents  of  Pelvis,    -  -    296 

5. — Absorbents  of  Organs  of  Digestion,  298 

6. — Absorbents  of  Viscera  of  Thorax,       -  -    303 

7. — Absorbents  of  Parietes  of  Trunk,  300 

8. — Thoracic  Ducts-,                       v             -  309 

BOOK  IX. 

OF  THE  NERVOUS  SYSTEM,       -  -    313 

PARTI. — General  Anatomy  of  the  Nervous  System,  -           313 

II. — On  the  Special  Anatomy  of  the  Central  Portion  of 

the  Nervous  System,      -  -    3^7 

CHAP.  I. — Medulla  Spinalis,  and  its  Membranes,  327 

Sect.  1. — Medulla  Spinalis,       -  -    327 

2. — Membranes  of  Spinal  Marrow,      -  -           333 

3. — Blood  Vessels  of  Medulla  Spinalis,     -  -    337 

CHAP.  II. — Encephalon,  -           338 

Sect.  1. — Membranes  of  Brain,                             -  -    339 

2. — Medulla  Oblongata,  -           349 

3. — Protuberantia  Annularis,  -    353 

4. — Cerebellum,  -           354 

5. — Cerebrum,      -  -    357 

6. — Nerves  of  Encephalon,     -  373 

7. — Arteries  of  Brain,        -  .    -    382 

PART  III. — Senses,                                                  -  -           387 

CHAP.  I. — Nose,     -  ...    337 

II.— Eye,  397 

Sect.  I. — Auxilliary  parts  of  Eye,  -    398 

2.— Eyeball,                -  413 


xlviii  CONTENTS. 


CHAP.  III.— Ear,     -  -                          -    433 

Sect.  1.— -External  Ear,       -  433- 

2. — Tympanum,  -    438 

3.— Labyrinth,  444 

4. — Nerves,  -    450 

PART  IV. — Special  Anatomy  of  Nerves,  453 

CHAP.  I. — Nerves  of  Encephalon,     -  453 

Sect.  1. — Nervus  Olfactorius,  453 

2. — Nervus  Opticus,  -             -    453 

3. — Nervus  Motor  Oculi,  454 

4. — Nervus  Trochlearis,  -    454 

5. — Nervus  Motor  Externus,   -  455 

6. — Nervus  Trigeminus,    -  ...    455 

7. — Nervus  Facialis,   -  465 

8. — Nervus  Hypoglossus,  -    468 

9. — Nervus  Accessorius,  469 

10. — Nervus  Glosso-Pharyngeus,  -                          -    470 

1 1  — Nervus  Pneumogastricus,  472 

CHAP.  II. — Sympathetic  Nerve,  -    477 

III. — Nerves  of  Medulla  Spinalis,  489 

Sect.  1. — Upper  Nine  Spinal  Nerves,  -                          -    489 

2. — Thoracic  Spinal  Nerves,  -  500 

3 1 — -Abdominal  Spinal  Nerves,  ...    503 


TREATISE    ON    ANATOMY, 


BOOK  I. 


PART  I. 

On  the  Anatomy  of  the  Skeleton. 

THE  skeleton  is  the  bony  frame- work  of  the  human  body; 
and,  by  its  hardness  and  form,  retains  in  proper  shape  the 
whole  fabric ;  affords  points  for  the  attachment  of  muscles ;  and 
protects  many  of  the  viscera.  Anatomists  call  the  bones,  along 
with  their  natural  connexions  of  ligaments,  cartilages,  and  sy- 
novial  membranes,  a  natural  skeleton ;  and  the  bones  only,  but 
kept  together  by  artificial  means,  an  artificial  skeleton. 

The  bones  are  inflexible,  and  in  a  recent  state  are  of  a  dull 
white  colour,  familiar  to  most  persons  from  its  being  the  same 
in  animals;  but  they  may  be  made  of  an  ivory  whiteness  by 
being  properly  macerated  and  prepared. 

The  regional  division  of  the  skeleton  is  into  Head,  Trunk, 
Superior  or  Thoracic,  and  Inferior  or  Abdominal  Extremi- 
ties. 

If  a  vertical  plane  be  passed  from  the  top  of  the  head  down- 
wards, through  the  middle  of  the  skeleton,  this  plane  will  divide 
the  latter  into  bilateral,  or  two  equal  portions,  called,  in  com- 
mon language,  the  right  and  the  left  side  of  the  body.  These 

VOL.  I.— 5 


50  SKELETON. 

two  sides  are  perfectly  alike  in  shape  and  size.*  Some  of  the 
bones  are  found  in  this  plane,  being  intersected  by  it  into  two 
equal  parts  or  halves :  others  are  somewhat  removed  from  it, 
and  are  in  pairs.  This  arrangement  antagonizes  the  two  sides 
of  the  body,  and  qualifies  it  for  all  its  motions. 


CHAPTER  I. 

OF  THE  BONES,  GENERALLY, 
SECT.  I. NUMBER,  TEXTURE. 

THE  number  of  the  bones  is  commonly  the  same  in  every 
person  of  middle  age ;  but  they  are  less  numerous  then,  than  in 
infancy,  from  several  of  them  having  been  originally  formed  in 
pieces  which  coalesce.  The  farther  fusion  in  advanced  life,  of 
contiguous  bones  into  each  other,  diminishes  still  more  their 
number.  It  is,  however,  generally  agreed  to  view  the  follow- 
ing as  distinct : — 

For  the  Head — An  occipital  bone,  a  frontal,  a  sphenoidal,  an 
ethmoidal,  two  parietal;  two  temporal,  each  containing  the 
small  bones  of  the  tympanum ;  two  superior  maxillary,  two 
palate,  two  malar  or  zygomatic,  two  nasal,  two  unguiform  or 
lachrymal  bones,  two  inferior  turbinated,  a  vomer,  and  an  in- 
ferior maxillary :  ?  .-^\, 

*  The  exact  harmony  or  symmetry  of  form  and  size,  between  the  two  sides  of 
the  body,  as  a  general  rule,  is  rather  hypothetical  than  real  in  nature.  It  is  a 
point  of  general  notoriety,  that  the  right  side  enjoys  more  force  than  the  left,  and 
this  will  "be  found  attended  with  greater  development.  There  are  few  persons 
that  have  not  the  face  and  the  spine  somewhat  out  of  shape  from  the  bones  on 
one  side  growing  larger  than  on  the  other,  the  right,  commonly,  prevailing  over 
the  left :  hence  we  sec  a  nose  somewhat  turned;  and  a  spine  curved,  the  convexity 
of  which  is  to  the  right  side,  with  the  attendant  consequences  on  the  position  of 
the  ribs— the  scapula)  and  the  sternvm.  This  condition  of  false  growth  is  exhi- 
bited, in  all  degrees,  from  a  deviation  almost  imperceptible  to  one  amounting  to 
deformity.  The  left  side  is  said,  also,  to  be  more  liable  to  diseases.  Copious  re- 
ports on  these  several  subjects  as  well  as  on  human  stature,  generally,  at  all 
ages,  have  been  made  by  the  French  Anatomists :  for  a  summary  exposition  of 
which,  see  Malgaigne,  Anat.  Chirurg.  Vol.  I.  Chap.  1.  Paris,  1838. 


SITUATION  OF  BONES.  51 

For  the  Trunk — Twenty-four  true  or  moveable  vertebrae,  one 
sacrum,  four  caudal  vertebra?  or  bones  of  the  coccyx,  two  inno- 
minata,  twelve  ribs  on  each  side ;  a  sternum,  in  three  pieces, 
however,  in  the  youthful  adult: 

One  hyoid,  in  three  pieces,  sometimes  five  in  the  adult,  and 
situated  in  the  throat:  ^  *^ 

The  remaining  bones  compose  the  limbs,  and  are,  therefore, 
in  pairs,  or  correspond  exactly  on  the  two  sides  of  the  body. 
They  are, 

For  the  upper  Extremities — The  clavicle,  the  scapula,  the  os 
humeri,  the  radius,  the  ulna,  the  eight  bones  of  the  carpus,  the 
five  bones  of  the  metacarpus,  the  two  phalanges  of  the  thumb, 
the  three  phalanges  of  each  of  the  fingers,  the  two,  and  some- 
times more,  sesamoid  bones: 

For  the  lower  Extremities — The  os  femoris,  the  tibia,  the  fibula, 
the  patella,  the  seven  bones  of  the  tarsus,  the  five  of  the  meta- 
tarsus, the  two  phalanges  of  the  big  toe,  the  three  phalanges  of 
each  of  the  smaller  toes,  and  the  two,  sometimes  more,  sesa- 
moids. 

There  are,  therefore,  twenty-two  bones  to  the  head,  not  in- 
cluding those  of  the  tympanum;  fifty-six  to  the  trunk  of  the 
body ;  one  insulated  bone  to  the  throat;  sixty-eight  to  the  two 
upper  limbs;  and  sixty-four  to  the  two  lower  limbs.  In  all,  two 
hundred  and  eleven.  The  redundancy  or  the  deficiency  of  the 
sesamoid  bones,  in  a  subject,  may  cause  this  number  to  be 
slightly  increased  or  diminished. 

The  situation  of  the  bones  varies;  some  are  profound,  while 
others  approach  very  near  to  the  surface  of  the  body.  They 
are,  as  stated,  either  symmetrical, — that  is,  consist  of  two  late- 
ral portions  precisely  alike, — or  else  in  pairs,  having  a  perfect 
correspondence  with  each  other.  The  symmetrical  or  bilateral 
bones  are  the  frontal,  the  occipital,  the  sphenoidal,  the  ethmoidal, 
the  vomer,  the  inferior  maxillary,  the  hyoid,  the  spinal,  and  the 
sternal ;  and  they  are  situated  under  the  middle  vertical  line  of 
the  body.  The  pairs  are  on  the  sides  of  the  middle  line,  more 
or  less  removed  from  it. 

The  long  bones  (ossalonga)  are  generally  cylindrical  or  pris- 
matic, and  have  their  extremities  enlarged  for  the  purpose  of 
articulating  with  adjoining  bones.  The  broad  bones  (ossa  lata) 


52  SKELETON. 

have  their  shapes  diversified  by  muscular  connexion  and  by  the 
forms  of  the  viscera  they  contain.  The  thick  bones  (ossa 
crassa)  are  situated  in  the  vertebral  column ;  and  in  the  hands 
and  feet ;  and  have  their  surfaces  very  irregular. 

The  bones  present,  on  their  periphery,  eminences  and  cavi- 
ties, a  proper  knowledge  of  which,  is  of  the  greatest  importance 
to  the  surgeon.  The  former  are  called  apophyses  or  processes, 
and  are  extremely  numerous  and  diversified:  they  serve  for  the 
origin  and  insertion  of  muscles,  and  for  furnishing  articular 
faces.  The  cavities  are  also  numerous :  some  of  them  are  su- 
perficial, and  serve  for  articular  surfaces;  others  for  the  origin 
of  muscles;  for  the  enlargement  of  other  cavities,  as  that  of  the 
nose  and  ear ;  and  for  purposes  which  will  be  mentioned  else- 
where. 

The  articular  ends  of  the  long  bones  are  called  epiphyses, 
from  their  being  formed  from  distinct  points  of  ossification, 
whereas,  the  shaft  of  the  bone  is  its  diaphysis  or  body,  being 
the  part  first  formed.  The  epiphysis,  therefore,  as  its  name 
implies,  grows  upon  the  other.  Many  processes  grow  after 
the  manner  of  epiphyses,  from  distinct  points  of  ossification, 
though  they  are  seldom  called  by  the  same  appellation.  This 
is  the  case  with  the  trochanters  of  the  os  femoris,  with  the  pro- 
cesses of  the  vertebra,  the  crista  of  the  ilium,  and  the  tuber  of 
the  ischium. 

Near  the  centre  of  some  bones  a  canal  is  formed  which  passes 
in  an  oblique  direction,  and  transmits  blood  vessels  to  their  in- 
terior. There  are  also,  at  the  extremities  of  the  long  bones,  at 
the  different  points  of  the  thick  ones,  and  near  the  margins  of 
the  flat  ones,  a  great  many  large  orifices,  which  principally 
transmit  veins:  in  addition  to  which,  a  minute  inspection  of  any 
bone  whatever,  will  show  its  whole  surface  studded  with  still 
smaller  foramina,  also  for  the  purpose  of  transmitting  blood 
vessels. 

The  density  of  bones  is  always  well  marked,  and  exceeds 
much  that  of  other  parts  of  the  body.  It  is,  however,  variable 
in  different  bones,  and  in  different  places  of  the  same  bone: 
hence  their  substance  has  been  divided  into  compact  and  .eel* 
lular,  of  which  the  former  is  external  and  the  latter  internal. 

The  cellular  structure,  or  substance,  grows  from  the  internal 


TEXTURE  OF  BONES.  53 

surface  of  the  other,  and  is  composed  of  filaments  and  small 
lamina?,  which  pass  in  every  direction,  by  crossing,  uniting,  and 
separating.  The  cells,  resulting  from  this  arrangement,  pre- 
sent a  great  diversity  of  form,  size,  and  completion.  They  are 
all  filled  with  marrow,  and  communicate  very  freely  with  each 
other.  The  latter  may  be  proved  in  the  boiled  bone,  by  the 
practicability  of  filling  them  all  with  quicksilver  from  any  given 
point ;  and,  indeed,  by  the  injection  of  any  matter  sufficiently 
fluid  to  run.  The  communications  between  them  are  formed 
by  deficiencies  in  their  parietes,  after  the  same  manner  that  the 
cells  of  sponge  open  into  each  other.  This  structure  does  not 
exist  in  the  earliest  periods  of  ossification,  when  the  bones  are 
cartilaginous  almost  entirely,  but  developes  itself  during  the 
deposite  of  calcareous  matter.  The  manner  of  its  formation 
is  imperfectly  understood,  though  it  may  possibly  be  the  result 
of  absorption,  and  it  is  not  completed  in  the  bones,  originally 
consisting  of  several  pieces,  till  they  are  consolidated  into  one. 

The  compact  substance  is  also  formed  of  filaments  arid  lami- 
nae, which  we  find  to  be  so  closely  in  contact  with  each  other, 
that  the  intervals  between  them  are  merely  microscopical  in 
the  greater  part  of  their  extent:  they  become,  however,  more 
and  more  distinct,  and  larger,  near  the  internal  surface;  and  at 
the  extremities  of  the  long  bones.  The  compact  tissue  is  gra- 
dually blended  with  the  cellular  structure,  or  lost  in  it.  Its 
filaments  are  directed  longitudinally  it)  the  cylindrical  bones, 
radiate  from  the  centres  of  the  fiat  ones,  and  are  blended  so  as 
to  render  it  impossible  to  trace  them  in  the  thick  ones.  This 
disposition  in  the  flat  bones  is  much  better  seen  in  early  life; 
subsequently,  it  becomes  indistinct.  The  compact  tissue,  par- 
ticularly in  the  cylindrical  bones,  has  in  it  a  multitude  of  lon- 
gitudinal canals,  visible  to  the  microscope,  and  some  of  them 
to  the  naked  eye,  which  contain  vessels  and  medullary  matter. 
Those  canals,  originally  described  by  Havers,  are,  according 
to  the  estimate  of  M.  Beclard,  about  one-twentieth  of  a  line  in 
diameter,  on  an  average;  but  they  are,  generally  larger  near 
the  interior  than  the  exterior  surface  of  the  bones,  and  have 
frequent  lateral  communications  with  the  cellular  structure,  and 
with  the  external  surface. 

The  compact  and  the  cellular  structures  present  themselves 

5* 


54  SKELETON. 

under  different  circumstances  in  the  three  species  of  bones.  The 
compact  has  an  unusual  thickness  in  the  bodies  or  diaphyses  of 
the  long  bones,  and  is  accumulated  in  quantities  particularly 
great  in  their  middle,  which,  from  its  position,  is  more  exposed 
than  their  extremities,  to  fracture  from  falls,  blows,  and  violent 
muscular  efforts.  But  as  this  texture  approaches  the  extremi- 
ties of  the  bones  it  is  reduced  to  a  very  thin  lamina,  merely  suf- 
ficient to  enclose  the  cellular  structure  and  to  furnish  a  smooth 
articular  face  for  the  joints.  The  cellular  structure,  on  the  con- 
trary, in  the  long  bones,  is  most  abundant  in  their  extremities, 
constituting  their  bulk  there,  and  is  least  so  in  their  bodies.  It 
is  so  scattered  at  the  latter  place  as  to  leave  a  cylindrical  canal 
in  their  middle,  almost  uninterrupted  for  some  inches.  This 
canal,  cellular  in  its  periphery,  has  its  more  interior  parts  tra- 
versed in  every  direction  by  an  extremely  delicate  filamentous 
bony  matter,  which,  from  the  fineness  of  its  threads  and  the 
wide  intervals  between  them,  has  been,  not  unaptly,  compared 
to  the  meshes  of  a  net,  and  is,  therefore,  spoken  of  especially 
under  the  name  of  the  reticulated  structure  or  tissue  of  the  bones, 
in  contra-distinction  to  the  cellular.  It  is  formed  on  the  same 
principle  with  the  latter;  and  though  the  term,  from  that  circum- 
stance, has  been  rejected,  upon  high  authority,  as  superfluous,  it 
appears  worthy  of  retention,  as  it  expresses  a  fact  of  some  im- 
portance, Too  weak  to  contribute  in  an  appreciable  degree  to 
the  strength  of  the  bone,  the  reticulated  tissue  seems  principally 
useful  in  supporting  the  marrow  and  in  giving  attachinent  to  its 
membrane.  The  extremities  of  this  cylindrical  canal  gradually 
disappear  by  becoming  more  and  more  cellular. 

In  the  fiat  bones,  the  compact  structure  forms  only  their  sur* 
face  or  periphery,  and  is  of  inconsiderable  but  generally  uniform 
thickness;  the  space  within  is  filled  up  with  the  cellular  struc? 
ture,  which  is  rather  more  laminated  than  it  is  in  the  long 
bones. 

In  the  thick  or  round  bones,  the  compact  structure  forms  their 
periphery  also;  but,  generally,  it  is  thinner  than  in  the  flat:  their 
interior  is  likewise  filled  up  by  the  cellular  structure,  and  does 
not  present  differences  of  importance,  from  the  ends  of  the  long 
bones. 

A  simple  experiment  on  any  of  the  cylindrical  bones  will  prove 
that  the  tumefaction  of  their  extremities  does  not  add  proporr 


TEXTURE  OF  BONES.  55 

tionately  to  their  weight,  as  one  inch  or  any  other  given  section 
of  the  compact  part  weighs  very  nearly  the  same  with  a  section 
of  equal  length  from  the  cellular  extremities.  The  swelling  at 
the  ends  of  the  bones  adds  much  to  the  safety  of  their  articular 
union,  as  the  extent  of  the  surfaces  is  thereby  much  increased, 
and,  consequently,  they  are  less  liable  to  displacement.  The  cy- 
lindrical and  the  cellular  cavities,  thus  formed  in  the  long  bones, 
by  increasing  the  volume  of  the  latter,  add  greatly  to  their 
strength  beyond  what  would  have  occurred,  had  the  same  quan- 
tity of  material  been  solid.  The  late  Dr.  P.  S.  Physick  demon- 
strated this  most  satisfactorily  by  a  scroll  of  paper,  which,  on 
being  rolled  up  successively,  into  cylinders  of  various  sizes,  has, 
like  a  lever,  its  power  of  sustaining  lateral  pressure  on  one  of  its 
extremities,  continually  increased  as  its  volume  or  diameter  is 
augmented,  until  the  latter  reaches  a  certain  extent.  The  same 
highly  distinguished  teacher  also  pointed  out  another  very  im- 
portant advantage  of  the  cellular  structure.  It  is  that  of  serving 
to  diminish,  and  in  many  cases  to  prevent  concussion  of  the 
brain,  and  of  the  other  viscera,  in  falls  and  in  blows.  The  opi- 
nion was  verified  by  his  demonstrating  the  momentum,  which  is 
communicated  through  a  series  of  five  ivory  balls  suspended  by 
threads,  when  one  of  them  is  withdrawn  from  the  others,  and 
allowed  to  impel  them  by  its  fall.  This  momentum  is  so  com- 
pletely transmitted  through  the  series,  that  the  ball  at  the  far- 
thest end  is  impelled  almost  to  the  distance,  from  which  the  first 
one  fell.  This  familiar  experiment,  used  as  a  preliminary  test 
to  the  accuracy  of  his  views,  was  immediately  succeeded  by  his 
substituting  for  the  middle  one  of  ivory,  a  ball  made  of  the  cel- 
lular structure  of  bone.  The  same  degree  of  impulsion  now 
communicated  at  one  end  of  the  series,  is  almost  lost,  or  rather 
neutralized,  in  the  meanderings  of  the  cellular  structure  of  the 
substitute;  and  particularly  if  the  latter  be  previously  filled  with 
tallow  or  well  soaked  in  water,  so  as  to  bring  it  to  a  condition 
of  elasticity  resembling  the  living  state. 

In  persons  of  advanced  age,  the  marrow  of  the  bones  becomes 
more  abundant,  and  their  parietes  thinner;  and  we  also  observe 
then,  that  the  bones  break  more  readily,  and  are  more  crum- 
bling, rotten,  or  soft,  than  during  the  anterior  periods  of  life. 
In  women,  after  the  critical  period  is  passed,  these  traits  are 
especially  developed,  and  the  compact  centres  of  the  long  bones 


56  SKELETON. 

have  their  texture  more  or  less  approximated  to  the  spongy  tis- 
sue. Mr.  Velpeau  (Anat.  Chirurg.)  says,  that  in  the  amphithe- 
atres of  Paris,  he  has  often  cut  easily  with  a  scalpel,  the  ends  of 
the  femur,  tibia,  humerus,  the  bodies  of  the  vertebrae  and  the 
tarsal  bones,  when  there  was  apparently  no  morbid  lesion  in  the 
skeleton. 


SECT.    II. COMPOSITION    OF    BONES. 

The  bones  under  every  modification  of  shape  and  mechanical 
arrangement,  are  constituted  by  precisely  the  same  elementary 
matters :  the  principal  of  which  are  an  animal  and  an  earthy 
substance,  in  intimate  combination.  Their  minute  analysis, 
according  to  Berzelius,  when  they  are  deprived  of  water  and 
of  marrow,  affords  32  parts  of  gelatine,  completely  soluble  in 
water;  1  part  of  insoluble  animal  matter;  51  parts  phosphate 
of  lime;  11  carbonate  of  lime;  2  fluate  of  lime;  1  phosphate 
of  magnesia;  1  soda  and  muriate  of  soda.  There  are  some 
other  ingredients  manifested  in  the  analysis  of  Fourcroy  and 
Vauquelin,  as  iron,  manganese,  silex,  alumine,  and  phosphate 
of  ammonia.  The  relative  proportion  of  the  above  ingredients 
is  not  uniformly  the  same,  as  the  bones  of  the  cranium,  and  the 
petrous  portion  of  the  temporal,  in  a  remarkable  degree,  have 
more  calcareous  matter  in  them,  than  the  other  bones  of  the 
same  skeleton.  There  is  also  a  considerable  diversity  in  indi- 
viduals, according  to  their  age  and  to  certain  morbid  affections. 

The  earthy  matter  gives  to  bones  their  hardness  and  want 
of  flexibility,  and  is  easily  insulated  from  the  other  by  combus- 
tion; which,  in  destroying  the  animal  part,  leaves  the  earthy 
in  a  white  friable  state,  but  preserving  the  original  form  of  the 
bone.  If  the  heat  be  of  a  high  degree,  the  calcareous  part 
becomes  vitrified,  and  its  cells  are  blended  by  fusion.  The 
action  of  the  atmosphere,  long  continued,  also  divests  the  bones 
of  their  animal  matter,  and  the  calcareous  then  falls  into  a 
powder.  If  the  bones  be  kept  beneath  the  surface  of  the 
ground,  by  which  they  are  less  affected  by  changes  in  tempe- 
rature and  moisture,  the  animal  matter  remains  for  an  immense 
number  of  years.  I  have  seen  in  the  Hunterian  Museum  of 
London,  preparations  of  the  teeth  of  the  Mastodon  or  Mam- 
moth, in  which  the  animal  matter  was  exhibited  entire,  notr 


COMPOSITION   OF    BONES.  57 

withstanding  the  great  lapse  of  years  since  it  was  in  a  living 
state :  and  a  repetition  here  of  the  same  experiments  on  the 
teeth  and  bones  of  the  same  animal  has  exhibited  the  same 
result.  I  was  also  informed  by  the  late  Mr.  Say,  a  distin- 
guished naturalist,  that  animal  matter  has  been  detected  in 
fossil  shells,  the  existence  of  which  was  probably  anterior  to 
that  of  the  human  family. 

The  phosphoric  acid  of  bones  gives  them  a  luminous  appear- 
ance at  night.  Bichat  says,  that  in  these  cases  he  has  found 
an  oily  exudation  on  the  luminous  points,  probably  from  the 
marrow  or  contiguous  soft  parts.  This  phenomenon  will 
account  for  many  of  the  superstitions  which  in  all  ages  have 
affected  ignorant  minds,  on  the  subject  of  burying  grounds. 

The  immersion  of  a  bone  in  diluted  muriatic  acid  is  the  best 
method  of  demonstrating  the  animal  part  in  a  separate  state. 
The  strong  affinity  of  the  acid  for  the  earthy  part,  and  the 
soluble  nature  of  the  salt  thus  formed,  leave  the  animal  matter 
insulated.  In  this  state  it  preserves  the  original  form  of  the 
bone,  is  cartilaginous,  flexible,  and  elastic.  The  action  of  hot 
water  alone,  upon  a  bone,  by  continued  boiling,  will,  from  the 
soluble  nature  of  the  cartilage,  separate  the  latter  from  the 
earthy  part,  and  convert  it  into  gelatine.  "  The  gelatine  may 
be  precipitated  afterwards  from  the  water  by  tannin.  The 
mode  of  this  combination  of  animal  and  of  earthy  matter  is 
not  understood,  but  it  is  generally  supposed  to  exist  by  the  ex- 
tremely small  cavities  of  the  former  receiving  earthy  particles, 
in  the  same  way  that  sponge  holds  water.* 

There  are  no  means  for  investigating  the  minute  anatomy 
of  the  bones  more  favourable  than  the  removal  of  the  earthy 

*  If  we  conceive  the  phosphate  of  lime  and  the  other  earthy  materials  of  bone 
to  be  in  a  state  of  solution  in  the  blood  and  serum  with  which  the  cartilaginous 
rudiment  of  the  bone  is  impregnated,  any  action  which  would  precipitate  the 
earthy  materials,  would  also,  of  course,  impregnate  the  cartilage  with  them,  and 
this  process  may  be  considered  as  completed  when  the  bone  acquires  its  proper 
consistence. 

Considering  cellular  substance  as  the  parenchyma  or  primordium  of  all  other 
parts,  it  is  probably  a  speculation  not  entirely  groundless,  that  every  peculiar 
tissue  or  glandular  texture  has  its  elements  precipitated  from  the  circulating 
fluid  in  a  manner  analagous  to  that  of  the  calcareous  part  of  bone.  This  idea 
also  affords  a  clue  to  a  result  almost  uniform  in  protracted  macerations  of  all 
tissues,  to  wit,  the  parts  being  brought  back  to  the  primordial  state,  by  the  pe, 
puliar  depositee  in  them  being  dissolved  in  the  water  and  removed, 


58  SKELETON. 

part  by  an  acid.  The  cartilage  thus  left  is  the  complete 
mould,  in  every  particular  of  form,  into  which  the  particles  of 
calcareous  matter  were  deposited.  In  this  state,  the  compact 
part  of  the  bodies  of  the  cylindrical  bones  may  be  separated 
into  laminae ;  and  these  laminae,  by  the  aid  of  a  pin  or  fine- 
pointed  instrument,  may  be  subdivided  into  filaments  or  threads. 

The  laminae,  though  enclosing  one  another,  are  not  exactly 
concentric.  I  have  observed,  that  the  more  superficial  come 
off  with  great  uniformity  and  ease  in  the  adult  bone,  but  the 
intertexture  continually  increases  towards  the  centre.  Bichat 
has  objected  to  this  dissection  of  the  bones,  that  the  laminae 
are  not  formed  in  nature,  but  factitiously,  by  the  art  of  the 
anatomist,  and  that  their  thickness  depends  entirely  on  the 
point  at  which  one  chooses  to  separate  them ;  they,  therefore, 
may  be  made  thick  or  thin  at  pleasure.  It  does  not  appear  to 
me  difficult  to  account  for  the  manner  in  which  this  laminated 
arrangement  is  produced.  The  longitudinal  filaments  of  the* 
bones  adhere  with  more  strength  to  each  other  at  their  sides 
than  they  do  to  those  above  or  below,  in  consequence  of  which 
a  plane  of  these  filaments  may  be  raised  at  any  place  and  of 
any  thickness.  This  fact  does  not  involve  the  inference  that 
the  bones  are  formed  by  a  successive  deposite  of  one  lamina 
over  another;  it  merely  inculcates  the  mode  of  union  between 
the  filaments  or  threads.  I  am,  however,  inclined  to  the  opi- 
nion that  the  periosteum  secretes  the  externaF  laminaB  in  the 
adult  bone,  inasmuch  as  they  separate  with  unusual  facility 
from  the  subjacent  one.  We  know  that  the  periosteum  has 
the  power  of  this  secretion,  as  a  laminated  deposite  of  bone  on 
the  roots  of  the  adult  teeth  frequently  met  with,  proves  without 
doubt,  as  also  the  phenomena  of  necrosis. 

The  disposition  of  the  cylindrical  bones  to  separate  into 
laminae,  is  constantly  manifested  in  such  as  are  simply  exposed 
to  the  atmosphere. 

The  opinion  of  the  laminated  and  filamentous  arrangement 
of  bones  has  been  very  generally  adopted  by  anatomists. 
Malpighi,  whose  name  is  inseparably  connected  with  minute 
investigations  in  anatomy,  taught  it.  Gagliardi,  also,  in  ad- 
mitting it,  thought  he  saw  pins  of  different  forms  for  holding 
the  laminae  together.  Havers  also  saw  the  laminated  and 
thread-like  structure.  In  short,  there  are  few  of  the  older 


COMPOSITION  OF  BONES.  59 

anatomists  who  have  not  adopted  fully  the  opinion.  Among 
the  moderns,  the  late  M.  Beclard,  the  distinguished  and  able 
Professor  of  Anatomy  in  the  School  of  Medicine  in  Paris,  says, 
that  when  the  earth  is  removed  from  bones  by  an  acid,  if  they 
be  softened  by  maceration  in  water,  the  compact  substance, 
which  previously  offered  no  apparent  texture,  is  separated  into 
laminae,  united  by  filaments;  the  laminae  themselves,  at  a  later 
period,  separate  themselves  into  filaments;  which,  by  a  farther 
continuation  of  the  process  swell,  and  become  areolar  arid  soft. 
A  long  bone  examined  after  this  process,  divides  its  body  into 
several  laminae,  the  most  external  of  which  envelops  the  rest; 
and  the  remainder,  by  rarefying  themselves  towards  the  extre- 
mities, are  continuous  with  the  cellular  structure  there. 

J.  F.  Meckel,  of  the  University  of  Halle,  has  furnished  the 
following  account  in  his  General  Anatomy  of  the  Bones : — 

"  The  filaments  and  the  laminae  which  constitute  the  bones 
are  not  simply  applied  one  against  the  other,  so  as  to  extend 
the  whole  length,  breadth,  or  thickness  of  a  bone,  or  to  go  from 
its  centre  to  the  circumference.  They  lean  in  so  many  differ- 
ent ways,  one  against  another,  arid  unite  so  frequently  by 
transverse  and  oblique  appendages  or  processes,  that  some 
great  anatomists,  deceived  by  this  arrangement,  have  doubted 
the  fibrous  structure  of  bones.  Nevertheless,  their  opinion  is 
not  perfectly  correct.  In  spite  of  those  inflections  and  anasto- 
moses of  fibres,  the  fibrous. structure  always  remains  very  ap- 
parent; and  one  is  warranted  in  saying,  that  the  dimension  of 
length  exceeds  the  two  others,  in  the  texture  of  many  bones. 
This  predominance  is  chiefly  well  marked  in  the  first  periods 
of  osteogeny ;  for,  at  a  later  time,  the  fibres  are  so  applied 
against  each  other,  as  scarcely  to  be  distinguished.  But  these 
longitudinal  fibres  never  exist  alone;  there  are  many  oblique 
or  transverse  ones  from  the  first  periods  of  ossification;  and 
they  are  even  from  the  beginning  so  multiplied,  that  the  num- 
ber of  longitudinal  fibres  does  not  prevail  over  them  so  much 
as  at  a  subsequent  period,  when  the  fibres  approach  nearer,  in 
such  way  that  the  transverse  become  oblique;  until  at  last, 
from  the  increase  of  the  bone,  the  latter,  at  first  view,  seems  to 
be  composed  only  of  longitudinal  fibres.  The  transverse  and 
oblique  fibres  do  not  form  a  separate  system;  but  continue  un- 


60  SKELETON. 

interruptedly  with  the  longitudinal,  which  they  unite  to  each 
other."* 

The  venerable  Scarpa,  some  years  ago,  advanced  opinions 
adverse  to  the  laminated  and  fibrous  or  filamentous  tissue  of 
bones  :f  the  latter  doctrine  he  was  induced  to  think  a  mere 
mistake,  arising  from  careless  observation.     Founding  his  own 
views  upon  what  he  had  seen  in  the  growing  bone, — in  the 
adult  bone  when  its  earthy  parts  were  removed  by  an  acid, — 
and  upon  certain  cases  of  disease  attended  with  inflammation 
of  the  bone;  he  denied,  without  reservation,  the  existence  of  la- 
minae and  fibres  in  bones,  declaring  that  even  the  hardest  of 
them  were  cellular  or  reticulated.     It  appears  to  me,  in  look- 
ing over  his  paper,  that  a  desire  to  overthrow  old  doctrines  and 
to  establish  new  ones,  has  induced  him  to  make  one  omission  in 
the  report  of  his  experiments,  otherwise  unaccountable  in  a  man 
of  his  general  intelligence  and  candour.     Having  softened  the 
cylindrical  bones  in  an  acid,  he  next  proceeds  to  a  long  conti- 
nued maceration  of  them  ;  he  finds,  as  other  persons  have  done, 
the  animal  part  of  the  bone  finally  resolving  itself  into  a  soft  cot- 
tony tissue.     He  has  made  but  one  jump  from  the  immersion  in 
the  acid  to  the  last  stage  of  the  process  of  maceration.     Now,  if 
in  a  short  time  after  the  bone  had  been  softened  in  the  acid,  he 
had  admitted  an  intermediate  observation,  he  would  no  doubt, 
like  all  other  inquirers,  have  found  that  the  animal  part  of  the  cy- 
lindrical bones  was  readily  separable  into  laminae ;  and  that  by  a 
pin  or  needle  these  laminae  could  be  split  into  fibres,  the  greater 
part  of  which  are  longitudinal;  and  that  pounding  the  ends  of 
these  fibres  with  a  hammer  would  resolve  them  into  a  very  fine 
penicillous  or  pencil-like  structure.     There  is  no  objection  to 
theuconclusion,  that  these  laminae  and  filaments,  as  a  final  con- 
dition, produce  a  very  fine  microscopical  cellular  arrangement, 
which  may  be  made  more  apparent  in  being  distended  by  the  de- 
velopment of  gaseous  substances,  arising  from  putrefaction  or 
maceration;  but  there  is  reason  for  a  decided  opposition  to  the 
assertion  of  there  being  no  fibres  in  bones,  when  we  have  daily 

*  Manuel  D'Anat.  Gen.  Descr.  et  Path,  traduit  dc  L'Allemand  par  Jourdan  et 
Breschet.  Paris,  1825. 

t  A  Scarpa.  De  penitiori  ossium  structura  cornrncntarius.  Leipp.  1795.  See 
also  Anatomical  Investigations,  Philadelphia,  1824,  by  the  late  J.  D.  God-man, 
M.  D.,  for  an  English  translation  of  the  same. 


COMPOSITION  OF  BONES,  61 

under  our  eyes  preparations  showing  them;  some  of  which  de- 
monstrate the  fibres  running  principally  longitudinally,  others 
spirally,  like  the  grain  of  a  twisted  tree,  and  others  having  a 
mixed  course.  Upon  the  whole,  the  description  cited  from 
Meckel,  exhibits  this  subject  in  a  just  and  accurate  manner. 

The  more  obvious  arrangement  of  the  cellular  and  compact 
structures  of  the  bones*  indicates  a  considerable  difference  in 
their  intimate  texture:  they  are,  nevertheless,  closely  allied; 
for  one  structure  is  converted,  alternately,  into  another  by  dis- 
ease, of  which  specimens  abound  in.  the  Wistar  Museum.  In 
both  cases,  from  the  fibres  or  filaments  are  formed  cells  which 
exist  every  where,  and  are  only  larger  and  more  distinct  in 
what  we  call  the  cellular  structure;  but  the  compact  part  has 
also  its  cells,  though  they  are  smaller,  more  flattened,  and  for 
the  most  part  microscopical* 

Organization  of  Bones. — The  blood  vessels  of  the  bones, 
though  small,  are  very  numerous.  This  is  well  established,  by 
the  success  of  fine  injections,  which  in  the  young  bone  commu- 
nicate a  general  tinge;  and  by  scraping  the  periosteum  from 
living  bones,  whereby  their  surface  in  a  little  time  becomes  co- 
vered with  blood,  effused  from  the  ruptured  vessels.  In  those 
operations  for  exfoliation  from  the  internal  surfaces  of  the  cy- 
lindrical bones,  where  it  is  necessary  to  excavate  the  bone  ex- 
tensively, in  order  to  remove  all  the  detached  pieces;  unless  the 
general  circulation  of  the  limb  be  previously  arrested  by  the 
tourniquet,  the  cavity  of  the  bone  is  flooded  with  blood.  Bi- 
chat  has  also  remarked,  that  the  blood  vessels  of  the  bones  be- 
come unusually  turgid  and  congested,  in  cases  of  drowning  and 
strangulation.  The  observations  in  1832,  on  cholera  in  Paris, 
showed  the  same  congestion  of  black  blood,  to  have  been  pro- 
duced by  that  disease. 

The  arteries  which  supply  the  bones,  from  their  mode  of  dis- 
tribution, are  referred  to  three  classes.  The  most  numerous 
and  the  smallest,  are  those  which  penetrate  from  the  periosteum, 
by  the  capillary  pores  found  over  the  whole  surface  of  the 
bones.  The  next  are  those  which  penetrate  the  larger  forami- 
na at  the  extremities  of  the  long  bones,  and  at  different  points 
of  the  surface  of  others.  And  the  third  class,  called  nourish- 
ing, amounts  to  but  one  artery  for  each  of  the  cylindrical  bones 

VOL.  L— 6 


62  SKELETON. 

which  penetrates  by  an  appropriate  canal,  as  mentioned,  com- 
monly near  the  centre  of  the  bone. 

The  arteries  of  the  first  two  classes  are  generally  extremely 
small.  They  ramify  upon  the  compact  and  cellular  structure, 
penetrating  it  in  every  direction.  At  death,  they  are  common- 
ly filled  with  blood,  which  renders  the  injection  of  them  diffi- 
cult. The  third,  or,  as  commonly  called,  the  nutritious  artery, 
is  of  a  magnitude  proportioned  to  the  bone  to  be  supplied.  Be- 
ing single  in  every  instance,  it  passes  through  the  compact  tis- 
sue, and  having  reached  the  medullary  cavity,  it  divides  imme- 
diately into  two  branches;  each  of  which  in  diverging  from  its 
fellow,  goes  towards  its  respective  extremity  of  the  bone.  These 
branches  ramify  into  countless  capillary  vessels  upon  the  mem- 
brane containing  the  marrow,*  and  finally  terminate  by  free 
anastomoses  with  the  extreme  branches  of  the  two  other  sys- 
tems. 

The  veins  of  the  bones  are  very  abundant :  they  are  uniform- 
ly found  in  company  with  the  branches  of  the  third,  or  nutri- 
tious arteries,  and  their  common  trunk  goes  out  at  the  nutri- 
tious foramen  into  the  general  circulation.  These  ramifications 
have  been  long  known,  and  bring  back  the  blood  from  the  me- 
dullary membrane  only.  The  veins  which  receive  the  blood  of 
the  other  arteries  do  not  attend  them,  and  were  first  of  all  found 
in  the  diploic  structure  of  the  cranium,  which  led  to  the  disco- 
very of  them  in  all  the  other  bones.  The  honour  of  the  ori- 
ginal observation  has  been  claimed  respectively  by  two  very 
distinguished  men  of  Paris,  MM.  Dupuytrent  and  Chaussier.J 
These  veins  issue  from  the  bones  by  numerous  openings  dis- 
tinct from  those  furnishing  a  passage  to  the  arteries.  This  cir- 
cumstance is  remarkably  well  seen  in  the  flat  and  thick  bones, 
and  at  the  extremities  of  the  cylindrical  ones.  Having  left  the 
bone,  they  terminate,  after  a  short  course,  in  the  common  ve- 
nous system.  They  arise  exclusively  from  the  spongy  and  com- 
pact structure,  by  extremely  fine  arborescent  branches,  which, 
uniting  successively,  form  trunks;  these  trunks  penetrate  the 
compact  tissue,  and  escape  from  the  bone  by  orifices  which  are 

*  Would  not  this  furnish  a  hint,  that  the  arteries  which  secrete  fat  are  diffe- 
rent from  other  arteries,  and  that  this  distinction  may  prevail  generally  ? 

t  Propositions  sur  quelques  points  d' Anatomic,  de  Physiologic,  &c.  Paris,  1803. 
}  Exposition  de  la  Structure  de  1'Enccphale.     Paris.,  1807. 


OF  THE  PERIOSTEUM.  63 

uniformly  smaller  than  the  bony  canals,  of  which  they  are  the 
terminations.  The  canals  are  formed  of  compact  substance, 
continued  from  the  external  surface  of  the  bone,  and  are  lined 
by  the  contained  veins.  The  parietes  of  the  canals  are  pene- 
trated by  smaller  veins  entering  into  the  larger.  M.  Dupuy- 
tren  is  of  opinion,  that  only  the  internal  membrane  of  the  ve- 
nous system  exists  in  this  set  of  veins;  that  it.  adheres  closely  to 
the  bone,  so  as  to  be  incapable  of  exerting  any  action  upon  the 
blood ;  that  it  is  very  thin,  weak,  transparent,  and  is  thrown 
into  numerous  valves. 

Lymphatic  vessels  are  generally  seen  only  on  the  surface  of 
the  bones.  Mr.  Cruikshank,  however,  on  one  occasion,  while 
injecting  the  intercostal  lymphatics,  passed  his  mercury  into  the 
absorbents  of  a  vertebra,  and  afterwards  saw  them  ramifying 
through  its  substance;*  a  fact  which,  along  with  what  is  known 
of  the  power  of  exfoliation  in  bones,  proves  sufficisntly  the  ex- 
istence of  such  vessels  in  them.  Nerves  have  also  been  traced 
into  them,  accompanying  the  nutritious  arteries.t 


CHAPTER  IL 

SECT.  I. OF  THE  PERIOSTEUM. 

THE  membrane  which  surrounds  the  bones  is  called  perios- 
teum, and  is  extended  over  their  whole  surface,  excepting  that 
covered  by  the  articular  cartilages.  As  this  membrane  ap- 
proaches the  extremities  of  the  bones,  it  is  blended  with  the  li- 
gaments uniting  them  to  each  other,  from  which  the  ancients 
adopted  the  opinion,  that  the  ligaments  and  periosteum  were 
the  same.  Many  fibres  pass  from  the  periosteum  to  the  bone, 
by  which  it  is  caused  to  adhere.  These  fibres  are  more  nume- 
rous and  stronger  at  the  extremities  than  in  the  middle  of  the 
cylindrical  bones ;  also  upon  the  thick  bones,  than  upon  the  flat 
ones.  The  blood  vessels  of  the  bones  accompany  these  fibres 

*  Anatomy  of  Absorbing  Vessels,  p.  98.   London,  1790. 
f  Beclard,  Elemens  d'Anatomie  Generale.  Paris,  1823. 


64  SKELETON. 

and  contribute  to  the  adhesion.  The  periosteum  is  united  to 
the  muscles  and  to  the  parts  lying  upon  it,  by  cellular  substance. 

The  adhesion  of  the  periosteum  to  the  bones  varies  in  the  se- 
veral periods  of  life.  In  infancy  it  may  be  separated  from  them 
with  great  facility:  in  the  adult  it  adheres  more  strongly  in  con- 
sequence of  its  internal  face  having  taken  on  a  secretion  of  bone, 
by  which  it  is  blended  intimately  with  the  bone  it  surrounds ; 
and  in  old  age  it  is  still  more  adherent,  from  the  progress  of  its 
ossification.  It  is  thick  and  soft  in  the  infant,  and  becomes 
ihinner  and  more  compact  as  life  advances. 

The  organization  of  the  periosteum  is  fibrous,  and  the  fibres 
pass  very  much  in  the  same  direction  with  the  fibres  of  the 
bones ;  excepting  the  flat  bones,  on  which  it  is  not  radiated. 
These  fibres  have  different  lengths,  the  more  superficial  are 
longer,  while  the  more  deeply  seated  extend  but  a  small  dis- 
tance. Inflammation  developes  the  fibres  in  a  striking  manner, 
by  occasionally  making  the  membrane  as  thick  as  an  aponeuro- 
tic  expansion. 

The  blood  vessels  of  the  periosteum  are  numerous,  and  can 
be  easily  injected.  They  come  from  the  contiguous  trunks, 
and  ramify  minutely,  into  a  vascular  net-work,  many  of  whose 
branches  penetrate  into  the  bone,  and  have  the  distribution  al- 
ready mentioned.  A  few  lymphatic  vessels  have  been  observed 
in  it.  Its  nerves  have  not  been  clearly  discovered,  though  the 
sensation  of  extreme  pain,  when  violence  is  done  to  it  in  an  in- 
flamed state,  may  be  thought  a  proof  of  their  existence.  In 
health  its  sensations  are  null,  or  extremely  obscure. 

The  periosteum  receives  the  insertion  of  tendons,  of  liga- 
ments, and  of  the  aponeuroses.  In  early  life,  owing  to  the 
slight  attachment  of  this  membrane  to  the  bones,  all  these  parts 
may  be  torn  from  them,  with  but  comparatively  little  force. 
Bichat*  having  advocated  the  opinion,  that  the  internal  laminas 
of  the  periosteum  become  ossified  in  the  adult,  considered  that 
as  a  means  by  which  all  the  afore-mentioned  insertions  into  it 
were  identified  with  the  bones.  This  will  account  for  the  great 
degree  of  tenacity  with  which  they  adhere,  and  the  immense 
force  they  are  capable  of  sustaining,  without  being  detached 
from  their  insertions.  In  this  tendency  to  ossify,  the  periosteum 

*  Anatomic  Generale. 


MEDULLA,  AND  ITS  MEMBRANE.  65 

manifests  a  great  similitude  to  other  fibrous  membranes,  as  the 
dura  mater,  the  sclerotica,  and  the  tendons. 

The  use  of  the  periosteum  is  to  conduct  the  blood  vessels  to 
the  bones,  to  protect  the  latter  from  the  impression  of  the  mus- 
cles, and  other  organs,  which  come  in  contact  with  them,  to 
keep  the  ossification  of  the  bones  within  its  proper  boundaries, 
to  give  shape  to  them,  and  to  secrete  bone  in  the  growing  state 
or  in  fractures;  and,  finally,  as  has  been  suggested  by  the  late 
Dr.  Physick,  it  exerts  a  very  happy  influence  in  turning  from 
the  bones  suppurations  in  their  vicinity,  which  would  otherwise 
be  pernicious  to  them. 

SECT.  II. OF  THE  MEDULLA,  AND  ITS  MEMBRANE,  CALLED  THE  IV- 

TERNAL  PERIOSTEUM. 

A  greasy  substance,  as  already  stated,  fills  the  cells  of  the 
bones :  it  does  not,  in  its  composition,  differ  from  common  fat : 
its  granules,  however,  seem  to  be  somewhat  finer.  From  its  re- 
semblance in  position  to  the  pith  of  vegetables,  it  has  obtained 
the  name  of  medulla  or  marrow.  It  is  contained  in  a  very  fine 
cellular  and  vascular  membrane,  lining  the  internal  cavities  of 
the  bones,  and  sending  into  their  compact  substance  very  deli- 
cate filaments.  The  existence  of  this  membrane  has  been  de- 
nied, but  it  may  be  established  by  sawing  a  bone  in  two,  and 
approaching  the  cut  end  to  the  fire,  so  as  to  melt  out  the  mar- 
row, or  by  immersing  it  in  an  acid,  in  which  case  the  mem- 
brane becomes  crisp  and  distinct.  Its  delicacy  is  so  extreme, 
that  it  can  only  be  compared  to  a  spider's  web.  In  this  state  it 
may  be  traced,  lining  the  whole  cylindrical  cavity  of  the  long 
bones,  and  extending  itself  to  their  extremities.  It  also  exists 
in  the  diploic  or  cellular  structure  of  all  the  other  bones ;  but  it 
is  scarcely  possible  to  demonstrate  it  there  in  a  very  distinct 
manner,  owing  to  its  extreme  tenuity. 

The  medullary  membrane  is  composed  principally  of  the  mi- 
nute and  numerous  blood  vessels  spent  upon  the  internal  sur- 
face of  the  bones,  aided  by  a  very  fine,  soft,  cellular  tissue, 
merely  sufficient  in  quantity  to  fill  up  the  meshes  between  the 
frequent  anastomoses  of  the  vessels.  From  the  latter  cause,  it 
is  compared  to  the  pia  mater  and  to  the  omentum.  It  has  been 
stated,  that  its  blood  was  derived  from  the  nutritious  artery, 

6* 


66  SKELETON. 

which  communicates  freely  with  the  other  arteries  of  the  bones. 
This  membrane  is  so  arranged  as  to  form  along  the  course  of 
the  blood  vessels  small  vesicular  appendages  which  contain  the 
marrow,  and  bear  some  analogy  to  a  thick  bunch  of  grapes* 
hanging  from  the  several  pedicles  of  the  stem. 

Its  nerves  are  extremely  small;  they  enter  by  the  nutritious 
foramen,  and  have  been  particularly  observed  by  Wrisberg  and 
Klint*  They  have  not  been  traced  ramifying  in  the  substance 
of  the  bone,  but  follow  for  some  distance  the  course  of  the  prin- 
cipal arteries. 

With  the  exception  of  Mr.  Cruikshank's  solitary  injection  of 
a  vertebra,  no  lymphatics  have  been  observed  satisfactorily  on 
this  medullary  membrane;  and  such  trunks  of  the  external  peri- 
osteum as  are  supposed  to  arise  from  the  medullary  membrane, 
have  not  been  traced  nearer  to  it,  than  the  orifice  of  the  nutri- 
tious canal. 

Some  differences  exist  in  the  nature  of  the  contents  of  the 
medullary  membrane;  for  example,  that  part  of  it  which  is  re- 
flected over  the  cells  in  the  extremities  of  the  long  bones,  and 
in  the  whole  interior  of  the  flat,  and  of  the  thick  ones,  contains 
a  much  more  bloody  and  watery  marrow,  than  what  is  found  in 
the  cylindrical  cavities  of  the  long  bones:  the  latter,  indeed,  re- 
sembles closely,  as  just  stated,  common  adeps,  presenting  no  es- 
sential differences  from  it.  These  circumstances  have  given 
occasion,  without  a  material  distinction  of  texture,  to  divide  the 
medullary  membrane  into  two  varieties. 

That  variety  contained  in  the  cellular  extremities  of  the  long 
bones,  and  in  the  spongy  bones  generally,  is  in  a  superior  degree 
vascular.  The  part  within  the  meshes  of  its  vessels  is,  however, 
so  imperfect,  that  Bichat  declared  his  inability  to  find  it,  and 
that  the  number  of  the  fine  vessels  was  what  gave,  fallaciously, 
the  appearance  of  a  membrane;  while,  in  fact,  the  intervals  be- 
tween them  were  large,  to  allow  the  fat  to  come  into  contact 
with  the  naked  bone.  The  probability  of  this  deficiency  is  con- 
firmed by  the  circumstance,  that  no  one  pretends  to  have  found 
a  membrane  in  the  microscopical  pores  of  the  compact  substance, 
yet  the  existence  of  fat  in  it  is  proved  by  its  becoming  greasy 
when  insulated  and  exposed  to  heat.  It  is  from  the  great  abun- 
dance of  blood  in  this  variety  of  the  medullary  tissue,  that  the 
proportion  of  its  adeps  is  small. 

*  Beclard,  loc..  ciU 


DEVELOPMENT  OF  BONES.  67 

The  second  variety  of  medullary  membrane  is  displayed  in 
the  cells  and  cylindrical  cavity  of  the  diaphysis  or  body  of  the 
long  bones.  Its  membranous  cells  communicate  freely  with  one 
another  when  the  membrane  is  entire;  but,  according  to  the  ob- 
servations of  Bichat,  not  with  such  as  are  in  the  epiphyses  of  the 
bones;  and  the  line  of  demarkation  is  abrupt  and  well  defined. 
This  is  proved  by  attempts  to  inflate  the  one  from  the  other;  the 
air,  in  such  cases,  passes  with  great  difficulty.  The  texture  of 
this  medullary  membrane,  from  its  extreme  delicacy  in  a  natural 
state,  is  rather  obscure,  but  it  is  occasionally  well  developed  in 
disease.  Its  sensibility  has  not  been  very  apparent  in  such 
cases  of  amputation  as  I  have  seen,  though  it  is  said,  by  some, 
to  be  extremely  exquisite.  In  whatever  degree  its  sensibility 
exists  in  different  subjects,  it  is  always  more  apparent  in  the 
middle  than  near  the  extremities  of  the  long  bones;  which  may 
be  accounted  for  by  its  nerves  always  entering  at  the  nutritious 
foramen,  and  extending  from  thence  towards  the  extremities. 

The  medullary  membrane,  besides  its  use  in  secreting  the 
marrow,  is  highly  serviceable  to  the  nutrition  of  the  bones,  as 
proved  in  the  experiments  of  Trojat,  who,  by  destroying  it, 
produced  their  death,  and  an  artificial  necrosis,  which  was  cured 
in  the  usual  way  by  a  new  secretion  of  bone  from  the  perios- 
teum. The  marrow  which  it  contains  in  the  adult  is  not  per- 
ceptible in  the  foetus.  Moreover,  the  quality  of  this  marrow  is 
varied  by  disease;  in  consumption,  dropsy,  and  other  ailments 
attended  with  great  emaciation,  a  considerable  part  of  it  is  ab- 
sorbed, and  a  serous  fluid  deposited  in  its  place;  a  circumstance 
well  known  to  those  who  clean  skeletons. 


CHAPTER  III.  ; 

ON  OSTEOGENY. 
SECT.  I. OF  THE  DEVELOPMENT  OF  THE  BONES. 

AT  birth,  though  the  skeleton  is  sufficiently  solid  to  preserve 
the  shape  of  the  individual,  yet  it  is  very  imperfect  in  many 


68  SKELETON. 

particulars,  which  will  be  pointed  out  more  in  detail  hereafter. 
At  present  it  may  be  stated,  that  the  ends  of  all  the  long  bones 
are  cartilaginous — the  carpus  and  tarsus  are  nearly  in  the  same 
state — the  vertebrae,  true  and  false,  have  their  processes  very 
imperfect;  and  consist,  each,  in  several  distinct  pieces,  united  by 
the  remains  of  the  cartilaginous  state.  Several  of  the  bones  of 
the  head  are  in  the  latter  condition;  and  the  sutures  are  so  im- 
perfect that  the  flat  bones  readily  ride  over  each  other  from  the 
thinness  of  their  edges,  and  also  have  the  angles  rounded,  which 
occasions  the  vacancies  called  fontanels. 

From  the  early  embryo  .state  to  the  completion  of  the  skele- 
ton, three  stages  are  observable  in  the  progress  of  ossification; 
the  first  is  mucous  or  pulpy,  the  second  cartilaginous,  and  the 
third  osseous. 

I.  The  mucous  stage  is  observable  at  a  very  early  period  after 
the  embryo   has  been  received  into  the  womb,  and  presents 
itself  under  two  modifications.     In  the  one,  from  the  general 
softness  of  the  whole  structure  of  the  embryo,  and  from   the 
apparently  homogeneous  nature  of  its  constituents,  the  mucous 
rudiments  do  not  distinguish   themselves  from  the  other  parts: 
This  condition,  however,  is  soon  changed  into  one,  and  that  be- 
fore the  expiration  of  the  first  month  of  gestation,  in  which  they 
assume  a  solidity  and  colour,  which   mark   them  off,  both   to 
the  eye  and  to  the  touch,  from  the  still  softer  parts  surrounding 
them. 

II.  About  the  expiration  of  the  first  month  the  mucous  stage 
is  converted  into  the  cartilaginous,  and  the   consistence   of  the 
bones  then  increases  continually  by  the  accumulation   of  gela- 
tine.    Bichat  makes  a  remark  on  this  subject  which  has  been 
confirmed  by  the  experiments  of  Scarpa,  though  erroneous  de- 
ductions have  been  made  by  the  latter:   that  we  do   not  see, 
during  the  formation  of  the  cartilages,  those  longitudinal  striae 
in  the  long  bones,  radiated  in  the  flat,  and  mixed  in  the  thick 
bones,  which  distinguish  the  osseous  state.     The   cartilaginous 
state  presents  another  peculiarity  worthy  of  observation:  all  the 
bones  which  in  a  more  advanced  stage  are  to  be  united  by  carti- 
lage, as  the  vertebrae,  those  of  the  pelvis,  and  of  the  head,  make, 


DEVELOPMENT  OF  BONES.  69 

in  their  groups,  respectively,  but  one  piece;  while  those  which 
are  to  be  united  by  ligament,  and  consequently  to  be  moveable, 
as  the  femur,  the  tibia,  the  clavicle,  and  so  on,  are  respectively 
insulated.  In  the  cartilaginous  state  the  bones  have  neither  cells 
nor  medullary  cavities,  and  consist  in  a  solid,  homogeneous  mass, 
the  form  of  which  is  sufficiently  definite;  and  has  its  surface 
covered  by  periosteum. 

The  flat  bones  of  the  cranium  seem  to  be  an  exception  to  the 
general  rule  of  a  preliminary  cartilaginous  state,  and  are  com- 
monly thought  to  be  such.  Their  appearance  is  delusive,  from 
the  cartilage  being  extremely  soft  and  thin,  and  concealed  by 
the  pericranium  on  the  one  side,  and  the  dura  mater  on  the 
other;  but  a  careful  dissection  enables  one  to  distinguish  it  from 
this  double  envelope.* 

III.  The  osseous  matter  begins  to  be  deposed  when  the  rudi- 
ments of  the  bone  have  become  entirely  cartilaginous,  with  the 
exception  of  a  few  mucous  points.  In  certain  bones  this  change 
is  observable  about  the  commencement  of  the  second  montht 
after  conception:  J.  F.  Meckel  has  placed  it  about  the  eighth 
week.  The  colour  of  the  cartilage  first  becomes  deeper;  and, 
in  the  region  where  ossification  is  to  commence,  is  of  a  well 
marked  yellow.  The  blood  vessels,  which  before  this  carried 
only  the  transparent  part  of  the  blood,  now  dilate,  so  as  to  admit 
the  red  particles,  and  a  red  point  is  perceived,  called  the  punc- 
tum  ossificationis,  from  its  receiving  the  first  calcareous  deposite. 
This  deposite  is  always  near  the  very  centre  of  the  cartilaginous 
rudiment,  and  not  at  its  surface:  the  portion  of  cartilage  nearest 
to  it  is  of  a  red  colour;  but,  a  little  farther  off,  opaque  and  hol- 
lowed into  canals.  The  ossification  increases  on  the  surface  of 
the  cartilage,  and  in  its  interstices,  by  continual  deposites,  which 
are  always  preceded  by  that  condition  just  mentioned.  The 
canals  of  the  cartilage  transmit  the  blood  vessels,  and  are  large 
at  the  beginning  of  ossification;  but,  as  the  process  advances  and 
is  completed,  they  diminish  gradually,  and  finally  disappear. 

The  progress  of  ossification  is  somewhat  modified  in  the  three 
classes  of  bones. 

*  Bichat,  loc.  cit.  t  Beclard,  loc.  cit.     Bichat,  loc.  cit. 


70  SKELETON. 

In  the  long  bones  a  small  ring  is  observed  to  form  early  near 
their  centre,  and  to  be  perforated  on  one  side  by  the  nutritious 
artery.  This  ring  has  its  parietes  thin,  but  broad,  and  its  cavi- 
ty is  the  beginning  of  the  medullary  canal.  It  is  formed  of 
very  delicate  fibres  which  advance  towards  the  extremities  of 
the  bone,*  and  at  the  same  time  increase  in  thickness;  so  that 
at  birth,  the  body  or  diaphysis  is  generally  finished.  Common- 
ly, at  a  period  subsequent  to  birth,  but  differing  in  the  several 
bones,  their  cartilaginous  epiphyses  also  begin  to  ossify,  by  the 
development  in  their  centre  of  points  of  ossification,  which  pre- 
sent the  phenomena  mentioned  in  the  last  paragraph  but  one. 
The  cartilaginous  state  of  the  epiphysis  gradually  disappears 
by  retiring  from  the  articular  end  of  the  bone  towards  its  dia- 
physis; and,  just  before  its  complete  removal,  it  appears  as  a 
thin  lamina,  gluing  the  end  or  epiphysis  of  the  bone  to  its  body. 
Several  of  the  apophyses  of  the  long  bones  are  also  formed  from 
distinct  points  of  ossification. 

The  ossification  of  the  flat  or  broad  bones  begins  by  one  or 
more  points,  according  to  the  bone  being  of  a  simple  shape  as 
the  parietal;  of  a  double  shape  or  symmetrical,  as  the  frontal, 
where  there  are  two  points  of  ossification ;  or  of  a  compound 
shape,  as  the  occipital  and  temporal,  where  there  are  several 
points.  The  commencement  of  ossification  in  them,  is  also 
manifested  by  the  appearance  of  a  red  vascular  spot  in  the 
cartilaginous  rudiment,  in  which  the  osseous  matter  is  depo- 
sited, and  from  which  it  progresses  in  radiated  lines.  The 
periphery  of  this  circle  of  rays  presents  intervals  between  the 
fibres,  giving  it  the  appearance  of  the  teeth  of  a  fine  comb: 
these  intervals  are  subsequently  filled  up  by  the  sections  of  radii 
starting  from  them,  and  so  on  successively  till  the  bone  is 
finished.  In  the  infantile  head  the  several  radii  grow  with  a 
pace  nearly  equal ;  so  that  where  the  bones  are  angular,  the 
angles  being  most  distant  from  the  centre  of  ossification  are 
finished  last  of  all,  from  which  result  the  fontanels.  Where  the 
bones  are  intended  to  be  kept  distinct  from  each  other,  their 
fusion  is  prevented  by  a  membranous  partition;  but  when  they 
are  to  coalesce  into  one  piece,  only  cartilage  is  found,  which  is 
subsequently  ossified. 

*  Bichat,  loc.  cit. 


GROWTH  OF  BONES.  71 

In  some  of  the  flat  bones,  as  the  sternum  and  the  sacrum, 
there  are,  first  of  all,  a  great  many  distinct  points  of  ossification, 
which  quickly  unite  into  a  smaller  number ;  they  then  remain 
stationary  for  a  number  of  years,  but  finally  all  unite  into  but 
one  piece. 

The  ossification  of  the  thick  bones  begins  by  one  or  more 
points,  according  to  the  simplicity  or  complexity  of  their  figures. 
The  bones  of  the  tarsus  and  of  the  carpus,  have  each  but  one 
point,  while  those  of  the  spine  have  several.  The  two  former, 
as  stated,  are  almost  entirely  cartilaginous  at  birth.  The  re- 
maining phenomena  of  ossification  in  these  several  bones  are  the 
same  as  has  been  mentioned. 


SECT.  II. ON   THE  MANNER  IN  WHICH  BONES  GROW. 

After  the  cartilaginous  condition  of  the  bones  has  been  sup- 
plied by  the  complete  deposite  of  osseous  matter,  and  they  are 
finished,  with  the  exception  of  the  epiphyses  being  fused  into  the 
respective  bodies,  the  bones  still  continue  to  grow  till  the  indi- 
vidual has  reached  a  full  stature.  This  is  effected  by  the  succes- 
sive addition  of  new  matter  to  the  old.  The  long  bones  lengthen 
at  their  extremities;  this  is  proved  by  the  following  experiment 
of  Mr.  John  Hunter.*  Having  exposed  the  tibia  of  a  pig,  he 
bored  a  hole  into  each  extremity  of  the  diaphysis,  and  inserted 
a  shot;  the  distance  between  the  two  shots  was  then  accurately 
taken.  Some  months  afterwards,  when  the  animal  had  increased 
considerably  in  size,  the  same  bone  was  examined,  and  the  shots 
were  found  precisely  at  their  original  distance  from  each  other, 
but  the  extremities  of  the  bone  had  extended  themselves  much 
beyond  their  first  distance  from  the  shots.  The  flat  bones  in- 
crease in  breadth  by  a  deposite  at  their  margins,  a  circumstance 
which  has  been  known  a  long  time,  but  it  required  the  ingenui- 
ty of  Mr.  Hunter  to  prove  conclusively  that  the  long  bones  in- 
crease in  length  by  a  similar  process,  and  not  by  interstitial  de- 
posite, as  Duhamel  thought.  This  observation  explains  most 
satisfactorily  the  use  of  the  cartilage  between  the  diaphysis  and 
the  epiphysis  in  all  bones ;  that  it  is  merely  interposed  for  the 

*  Transactions  of  a  Society  for  Improvement,  vol.  ii.  London,  1800.  Experi- 
ments and  Observations  on  the  Growth  of  Bones. 


72  SKELETON. 

purpose  of  offering  the  least  possible  resistance  to  the  new  os- 
seous fibres,  which  grow  from  the  epiphyses  and  from  the  dia- 
physes:  and  that  it  is  kept  for  this  end,  without  any  material 
change  in  thickness,  from  the  fourth  or  fifth  year  to  the  six- 
teenth or  eighteenth,  when  it  disappears,  because  there  is  no 
longer  any  use  for  it,  in  consequence  of  the  bones  having  at- 
tained their  full  length. 

The  epiphyses  are  then  manifestly  intended  to  favour  the 
elongation  of  the  bodies  and  the  development  of  the  extremities 
of  the  long  bones,  to  suit  the  same  purposes  in  some  of  the  flat 
bones,  as  those  of  the  pelvis,  and  to  permit  the  general  deve- 
lopement  of  the  bodies  of  the  vertebras.  The  ossification  of  the 
epiphyses  commences  in  some  bones  about  fifteen  days  before 
birth,  as  in  the  inferior  extremity  of  the  thigh  bone,  and  in 
others,  as  those  of  the  ossa  innominata,  not  till  the  fifteenth 
year  or  thereabouts.  Many  of  the  processes  from  the  bones, 
are  also  epiphyses,  as  the  trochanters  of  the  os  femoris,  the 
tuber  of  the  ischium,  the  acromion  scapulae,  the  seven  processes 
of  a  vertebra,  and  so  on,  and  are  developed  in  the  same  way. 
The  time  at  which  they  all  are  thoroughly  fused  into  the  bones 
to  which  they  belong,  extends  from  the  fifteenth  to  the  twenty- 
fifth  year;  depending  upon  the  individual  bone,  and  upon  vari- 
eties of  constitution  in  different  persons :  though  this  process 
may  be  considered  as  completed,  generally,  in  the  female  at 
the  age  of  eighteen,  and  in  the  male  at  twenty-one. 

The  increase  in  thickness  of  every  bone  depends  upon  a 
continued  secretion  from  the  internal  surface  of  the  periosteum, 
at  first  soft  and  mucous,  then  osseous :  when  this  secretion  is 
arrested,  the  bones  cease  to  grow  in  thickness,  which  com- 
monly occurs  some  time  after  they  have  attained  their  full 
length.  The  changes  which  subsequently  take  place  in  them 
are  those  of  interstitial  deposite  and  absorption :  the  former  is 
well  exemplified  in  inflammation  of  the  bones,  and  in  spina 
ventosa ;  the  latter  in  the  diminution  of  the  bones  in  extreme 
old  age,  and  in  the  loss  of  the  alveolar  processes. 

There  is  no  period  of  life  in  which  this  interstitial  absorption 
and  deposite  is  not  continually  occurring,  but  it  is  much  more 
rapid  in  young  and  growing  animals  than  in  the  adult  and  old. 
The  experiments  of  Mr.  Hunter  and  of  Duhamel,  show,  that 
when  a  growing  animal  is  fed  upon  madder,  (rubia  tinctorum,) 


GROWTH    OF    BONES.  73 

the  bones  are  quickly  coloured  by  it;  when  the  madder  is 
withheld,  the  bones  become  again  white;  and  that  the  first 
appearance  of  the  restoration  of  the  latter  is  manifested  by  a 
white  lamina  being  deposited  on  their  surface.  The  madder, 
under  such  circumstances,  is  a  long  time  in  getting  out  of  the 
bones.  I  fed  a  young  pig  for  one  month  on  it,  mixed  with 
other  food.  At  the  expiration  of  the  succeeding  five  months, 
the  animal,  having  grown  very  considerably,  was  killed.  The 
interior  lamince  of  all  the  bones  continued  to  be  deeply  tinged, 
while  their  surface  from  the  deposite  of  new  bone  had  become 
white.  From  this  it  would  appear  that  deposite  is  a  very  per- 
manent thing  in  bones :  it,  of  course,  must  prevail  much  over 
absorption,  else  their  growth  would  be  arrested. 

At  the  same  time  that  the  periphery  of  each  bone  is  increas- 
ing in  its  dimensions,  the  medullary  canal  is  also  augmenting : 
this  arises  from  an  absorption  going  on  internally,  while  the 
deposite  is  making  externally.  Duhamel*  proved  this  by  a  cu- 
rious experiment.  He  surrounded  a  cylindrical  bone  of  a 
young  animal  with  a  metallic  ring;  on  killing  the  animal  some 
time  afterwards,  he  found  the  ring  covered  externally  by  a  se- 
cretion of  bone,f  owing  to  the  growth  of  the  latter,  and  the 
medullary  canal  as  large  as  the  ring  itself.  Notwithstanding 
the  obvious  conclusion  from  this  experiment,  he  made  the  mis- 
take of  supposing  that  the  bone  had  enlarged  by  expansion,  and 
not  by  a  deposite  externally  with  an  absorption  internally. 

As  the  individual  advances  in  life,  the  cylindrical  canal,  in 
the  centre  of  the  long  bones,  continues  to  enlarge  in  size  by  the 
internal  absorption  :  so  that  the  parietes  of  the  bones,  which  in 
early  life  were  much  thicker  than  the  canal,  and  in  the  adult 
about  the  same  diameter,  become  exceedingly  thin  in  old  age; 
resembling  thereby  a  stalk  of  Indian  corn,  with  the  pith  scoop- 
ed out.J  The  cells  of  the  cellular  structure  in  the  several 
bones  also  enlarge,  whereby  the  whole  weight  of  the  bones  is 
much  decreased  in  the  very  aged.  In  the  parietes  of  the  cra- 

*  Mem.  de  1'Acad.  Roy.  des  Sciences,  an.  1739-41-43-46. 

t  If  a  string  be  tied  around  a  growing  tree,  the  same  thing  takes  place,  and  it 
is  finally  shut  up  in  the  ligneous  part. 

t  There  are  several  examples  of  this  in  the  Anatomical  Museum.  More  rarely 
the  reverse  takes  place,  and  the  cavity  is  filled  up :  of  this  there  are  also  speci- 
mens. 

VOL.  I.-7 


74  SKELETON. 

nium  there  is  rather  a  tendency  to  the  absorption  of  the  diploe, 
and  the  approximation  of  their  tables. 

The  bones,  also,  become  more  brittle  in  old  age,  in  conse- 
qneuce  of  the  increase  of  calcareous,  with  a  diminution  of 
gelatinous  matter.  The  reverse  being  the  case  in  infancy, 
they  are  more  flexible  than  in  the  adult,  and  can  even  bear  to 
be  twisted  or  bent  without  breaking.* 

SECT.  III.  — ON  THE  FORMATION  OF  CALLUS. 

As  this  is  a  consequence  of  bones  being  fractured,  and  a  mode 
that  nature  takes  to  repair  the  accident,  there  is  some  resem- 
blance between  it  and  the  primitive  formation  of  bone.  Owing 
to  the  rupture  of  the  blood  vessels  of  the  bone;  of  those  of  the  pe- 
riosteum, and  of  the  medullary  membrane;  and  frequently  of  the 
vessels  of  contiguous  parts,  the  first  effect  of  the  accident  is  an 
effusion  of  blood  into  the  cavity  of  the  fracture.  The  several 
contiguous  soft  parts  then  swell,  become  hardened  and  inflamed; 
and,  in  the  mean  time,  an  absorption  of  the  blood  is  proceeding, 
while  an  effusion  of  coagulating  lymph  from  the  ruptured  ves- 
sels occurs  in  the  cavity  of  the  fracture.  A  ring,  the  thickest 
part  of  which  is  precisely  over  the  seat  of  the  fracture,  is  formed 
by  the  lacerated  parts  ossifying:  there  is  also  formed  in  the  in- 
terior of  the  bone  a  sort  of  osseous  pin.  Till  this  moment  the 
bone  itself  remains  unchanged,  with  the  exception  of  a  coating 
of  coagulating  lymph  on  its  broken  faces;  but  now  its  extremi- 
ties begin  to  coalesce  or  fuse  themselves  into  each  other,  the  su- 

*The  reported  instances  are  now  numerous,  where,  from  a  defective  organiza- 
tion of  bone,  fracture  is  produced  from  very  trivial  causes;  and  this  state  is  not 
confined  to  any  particular  age,  for  it  extends  from  infancy  to  advanced  life.  I 
have  attended  a  fractured  os  femoris  in  a  child  of  two  years,  from  a  stumble  in 
walking  across  a  carpeted  floor.  In  another  child  the  os  femoris  was  broken,  so 
far  as  could  be  learned,  by  the  nurse  stooping  to  reach  something  from  the  floor: 
the  same  child  had  both  clavicles  broken,  without  any  one  knowing  when  or 
where:  the  left  side  was  flattened,  from  the  fracture,  probably  a  partial  one,  of 
several  ribs,  equally  inexplicable.  In  a  third  child  the  tibia  was  broken  from  a 
trifling  fall  on  the  floor,  and  the  clavicle  from  striking  the  shoulder  moderately 
against  the  rounded  back  of  a  chair. 

In  these  several  instances  the  fragility  may  arise  cither  from  a  defective  rela- 
tion of  the  constituents  of  the  bone  to  each  other,  by  a  deficiency  of  animal  mat- 
ter, which  diminishes  the  tenacity  of  the  bone,  or  it  may  arise  from  attenuation 
merely  of  the  bone,  leaving  its  points  too  thin  for  ordinary  accidents. 


FORMATION  OF  CALLUS.  75 

perfluous  bony  matter  (the  ring  and  the  pin)  being  no  longer 
necessary, 'is  absorbed,  and  the  cavity  of  the  bone  with  the 
membranes  of  the  latter  is  re-established.*  In  this  case  it  will 
be  seen  that  the  deposite  of  coagulating  lymph  into  the  cavity 
of  the  fracture,  corresponds  with  the  mucous  rudiments  of  the 
foetal  bone,  and  that  the  remaining  phenomena  of  ossification  are 
the  same. 

Some  physiologists  have  attempted  to  give  to  the  periosteum 
the  exclusive  credit  of  the  formation  of  callus:  the  view  is  erro- 
neous, because  experiments  show,  that  even  where  the  perios- 
teum is  stripped  designedly  from  the  fractured  ends  of  bones, 
they,  nevertheless,  unite,  and  the  periosteum  is  restored  when 
the  callus  is  formed.  The  probability  then  is,  that  all  the  blood 
vessels  (from  whatever  source  they  come)  which  penetrate  the 
organized  coagulating  lymph  secreted  between  the  fractured  ex- 
tremities, convey  and  deposite  calcareous  matter. 

The  celebrated  Bichat  and  some  others,  were  of  opinion,  that 
in  every  case  of  fracture  where  the  ends  of  the  bones  are  not 
kept  in  contact,  granulations  spring  up  from  the  ruptured  sur- 
faces of  the  bone,  and  of  its  membranes;  that  these  granulations 
first  receive  into  their  interstices  a  soft  gelatinous  deposite,  then 
a  cartilaginous  one,  and,  finally,  a  calcareous  one,  by  which  the 
bone  is  united.  This  process,  however,  is  much  more  common 
in  compound  fractures  which  suppurate,  and  may  be  considered 
rare  in  simple  ones. 

When  the  calcareous  matter  begins  to  take  a  place  in  a  form- 
ing callus,  if  the  part  be  much  moved,  the  process  is  arrested, 
the  blood  vessels  no  longer  deposite  even  if  they  carry  calca- 
reous materials,  and  an  artificial  joint  is  formed.  The  proper 
period  of  restoration  being  once  passed,  the  vessels  sink  into  an 
inactive  state  from  which  they  have  little  or  no  disposition  to 
rouse  themselves.  Under  these  circumstances,  Dr.  Physick 
proposed,  many  years  ago,  the  introduction  of  a  seton  through 
the  cavity  of  the  fracture,  and  the  retaining  of  it  there  for  a  long 
time,  for  the  purpose  of  stimulating  the  vessels.  The  plan  has 


*  J.  Hunter,  paper  by  Mr.  Home,  in  Trans,  of  Society  for  Improvement.     Lon- 
don, 1800. 


76  SKELETON. 

now  been  repeatedly  tried,  with  complete  success,  on  the  cylin- 
drical bones,  and,  in  one  instance,  upon  the  lower  jaw.* 

Callus  is  formed  much  more  speedily  in  young  persons  than 
in  old:  occasionally,  however,  we  meet  with  cases  in  which  the 
rapidity  of  its  deposite  in  the  latter  is  remarkable.  I,  for  ex- 
ample, treated,  in  1826,  a  female  of  ninety,  for  a  simple  frac- 
ture of  the  os  humeri,  which  was  cured  at  the  end  of  five 
weeks. 

*  Dorsey's  Elements  of  Surgery.  Philadelphia  Med.  and  Phys,  Jour.  &c. 
There  is  now  in  the  possession  of  Dr.  J.  Randolph,  the  son-in-law  of  the  late 
Dr.  Physick,  the  os  humeri  upon  which  this  experiment  was  first  tried,  and 
which  shows,  very  satisfactorily,  the  state  of  union  :  a  hole  is  still  left  which 
the  seton  occupied, 


BOOK  I. 


PART  If. 

Of  the  Bones,  individually. 

THE  several  textures  of  the  body  are  so  intermixed,  that  the 
consideration  of  one  alone,  pursued  through  all  its  applications, 
excludes  for  the  time,  rather  artificially,  some  one  or  more  of 
the  others.  This  circumstance,  inseparable  from  a  clear  ac- 
count, has  always  perplexed  writers  on  anatomy,  and  left  them 
under  various  impressions  concerning  the  best  point  of  depar- 
ture and  method  for  pursuing. their  descriptions.  Reasons  of 
value  may  be  urged  for  almost  any  arrangement :  each  one 
will  have  some  peculiar  advantages  that  the  others  have  not, 
and  which  will  cause  it  to  appear  to  the  understandings  of  its 
advocates,  superior  to  the  rest.  For  a  course  of  study  which 
is  intended  to  be  physiological  and  surgical  in  its  combinations, 
the  usual  practice  of  beginning  with  the  skeleton  is,  perhaps, 
the  most  advantageous;  the  young  student  will,  however,  un- 
derstand that  if  the  skeleton  have  any  natural  claim  to  this 
precedence,  it  is  principally  from  its  furnishing  those  land- 
marks, as  it  were,  to  which  we  refer  the  situation  of  other 
parts,  and  that  it  is  only  conceded,  for  the  purpose  of  laying  a 
foundation  for  their  more  easy  and  intelligible  description  sub- 
sequently. The  human  frame  may  be  compared  to  an  extend- 
ed landscape,  the  multiplicity  of  whose  features  and  the  variety 
of  objects  spread  over  whose  surface,  collectively,  bewilder  the 
beholder;  but  by  seizing  first  on  its  prominent  outlines,  marking 
the  course  of  its  mountains  and  ridges,  and  determining  the 
bearings  of  the  several  objects  according  to  them,  we  become 
able,  at  length,  to  define  not  only  to  ourselves,  but  to  others, 
the  precise  position  of  each  point,  or  each  object  which  may 
become  the  subject  of  inspection. 


78  SKELETON. 

Unfortunately, '  the  minuteness  with  which  the  skeleton  is 
described  has  been  decried  as  useless,  but  the  zealous  and  rea- 
sonable student  ought  to  bear  in  mind — that  the  only-rational 
plan  of  reducing  a  dislocated  joint  must  depend  upon  a  proper 
knowledge  of  its  articular  faces;  that  many  of  the  great  phe- 
nomena of  life  depend  essentially  upon  the  arrangement  of  the 
skeleton;  that  locomotion  is  inseparably  connected  with  it; 
and  that,  in  short,  it  has  a  bearing  upon  almost  every  animal 
operation.  With  these  facts  impressed  upon  him,  he  will  be 
prepared  to  give  the  history  of  the  skeleton  a  full  and  perfect 
attention. 


CHAPTER  J. 

THE  TRUNK. 

THE  trunk  is  constituted  by  the  Spine,  the  Thorax,  and  the 
Pelvis. 

SECT.  I. THE  SPIKE. 

The  spine,  (Columna  Vertebralis,  Rachis,)  is  placed  at  the 
posterior  part  of  the  trunk,  and  extends  from  the  head  to  the 
inferior  opening  of  the  pelvis.  It  consists  of  twenty-eight  or 
nine  distinct  pieces,  of  which  the  upper  twenty-four  are  true, 
or  moveable  vertebrae.  The  twenty-fifth  is  the  sacrum,  or  the 
pelvic  vertebra,  which  is  fixed;  and  the  remainder  are  the 
caudal  vertebrae  or  the  coccyx. 

On  the  posterior  face  of  the  spine,  each  of  the  true  vertebrae 
is  seen  to  contribute,  by  a  long  process,  to  that  ridge  which  is 
so  readily  felt  beneath  the  skin,  and  from  which,  probably,  the 
name  of  spine  was  derived.  The  spine  increases  gradually  in 
size  from  the  first  to  the  last  true  vertebra.  The  upper  part 
of  the  sacrum  is  extended  laterally  much  beyond  the  latter, 
afterwards  the  spine  diminishes  abruptly  to  the  extremity  of 
the  coccyx.  The  spine  has  several  curvatures,  which  are  best 
marked  in  the  erect  position.  For  example,  the  lower  part  of 
the  cervical  portion  is  convex  anteriorly,  and  concave  behind — 
the  thoracic  part  is  concave  in  front,,  and  convex  behind — the 


THE    SPINE.  79 

lumbar  portion  is  convex  in  front,  and  concave  behind — the 
pelvic  and  caudal  portion  is  concave  in  front,  and  convex  be- 
hind. This  arrangement  is  the  result  of  the  different  degrees 
of  thickness  in  the  bodies  of  the  vertebrse,  and  especially  in  the 
fibro-cartilages  which  unite  them  to  each  other.  Wherever 
these  cartilages  are  thin  at  their  anterior  margin,  there  is  a 
concavity ;  but  where  they  are  thick  at  the  same  point,  there 
is  a  convexity. 

There  are  seven  vertebrae  to  the  neck,  called  cervical; 
twelve  to  the  thorax,  called  dorsal;  and  five  to  the  loins, 
called  lumbar.  In  reckoning  the  number  of  the  vertebrae,  the 
one  next  to  the  occiput  is  always  the  first;  and  so  on,  succes- 
sively, to  the  last.  Albinus,  however,  has  departed  from  this 
rule,  and  counts  them  from  below,  upwards. 

General  Characters  of  a  Vertebra. 

A  vertebra  (verttbre)  consists  in  a  body,  in  seven  processes 
or  extremities,  and  in  a  canal  or  foramen  for  lodging  the  spinal 
marrow. 

The  body  of  a  vertebra  is  at  its  fore  part ;  it  is  somewhat  cy- 
lindroid  or  oval,  but  varies  considerably  from  these  figures  ac- 
cording to  its  position  in  the  spine.  The  anterior  part  of  the 
body  is  convex ;  but  the  posterior  part  is  concave,  where  it  con- 
tributes to  the  spinal  canal.  The  superior  and  inferior  surfaces 
are  fiat,  with  the  exception  of  a  ridge  of  hard  bone  at  the  cir- 
cumference, more  elevated,  and  not  so  extended  in  some  bones 
as  in  others.  These  ridges  are,  in  young  subjects,  epiphyses. 
There  are  many  foramina,  large  and  small,  to  be  seen  on  the 
front  and  back  surfaces  of  the  bodies.  They  transmit  arteries 
and  veins,  and  some  of  them  are  used  for  fastening  the  liga- 
ments of  the  spine.  On  the  posterior  face  of  the  body  there 
are  two  foramina  larger  than  the  others,  occupied  by  veins 
coming  from  the  interior  of  the  vertebra.  These  veins  corre- 
spond with  the  diploic  sinuses  in  the  head,  and  have  been  parti- 
cularly described  by  M.  Breschet,  of  Paris,  in  a  thesis  present- 
ed to  the  School  of  Medicine  in  1819. 

The  processes  are  placed  a.t  the  posterior  part  of  the  vertebra. 


80  SKELETON. 

Of  these  there  are  four  oblique  or  articulating  processes,  which 
articulate  with  the  corresponding  ones  of  the  bones,  above  and 
below;  two  transverse  processes,  which  project,  one  on  either 
side,  from  between  the  oblique  processes;  and  one  spinous  pro- 
cess, which  is  placed  on  the  middle  of  the  bone  behind.  The 
two  oblique,  and  the  transverse  process  on  each  side,  come  from 
a  common  base  or  root  that  arises  from  the  lateral  posterior  part 
of  the  body,  and  present  collectively  a  very  irregular  appear- 
ance. Their  faces  and  inclinations  are  much  modified  in  the 
several  vertebrae.  The  spinous  process  is  also  much  modified 
in  regard  to  size,  shape,  and  inclination. 

The  body  and  processes  form  the  periphery  of  the  foramen 
for  the  spinal  marrow,  and,  by  their  thickness  and  strength, 
afford  an  excellent  protection  to  the  latter.  This  spinal  fora- 
men is  of  a  triangular  shape,  presenting  its  base  in  front  and  its 
apex  behind.  It  is  considerably  larger  than  the  spinal  marrow 
of  the  part,  including  its  vessels,  membranes,  and  the  nerves 
that  proceed  from  it;  in  this  respect  the  foramen  differs  very 
materially  from  the  cavity  of  the  cranium,  which  is  exactly 
filled  by  the  brain. 

At  the  upper  part  of  the  spinal  foramen  of  a  vertebra,  between 
the  body  and  the  upper  articulating,  or  oblique  process,  is  a 
groove.  There  is  another  groove  between  the  lower  oblique 
process  and  the  body.  These  grooves,  by  the  approximation  of 
the  contiguous  vertebrae,  are  converted  into  perfect  holes,  called 
inter-vertebral  foramina,  and  are  for  the  transmission  of  the 
spinal  nerves  and  blood  vessels. 

The  bodies  of  the  vertebrae  are  extremely  light  and  spongy, 
being  formed  principally  of  the  cellular  matter  of  bone,  and  are 
covered,  with  the  exception  of  their  upper  and  lower  surfaces, 
with  a  very  thin  lamella  of  compact  substance.  The  processes, 
for  the  most  part,  have  a  thick  and  compact  structure,  enabling 
them  to  sustain  conveniently  the  weight  of  the  body  and  the  ac- 
tion of  the  different  muscles,  as  applied  to  them. 

Of  the  Cervical  Vertebra,  generally. 

The  cervical  vertebrae  differ  among  themselves,  but  are  dis- 
tinguished by  certain  common  properties  from  the  other  bones, 


THE  SPINE.  81 

of  the  spine.  Their  bodies  and  processes  are  small,  but  the 
spinal  foramen  is  large,  so  as  to  admit  of  much  motion,  without 
pressing  on  the  spinal  marrow.  The  fore  and  back  parts  of  the 
body  are  more  flattened.  The  upper  face  is  concave  transverse- 
ly, being  bounded  on  each  side  by  a  ridge  of  bone;  the  lower 
face  is  concave  from  before  backwards,  and  is  bounded  by  a 
ridge  before  and  behind.  This  arrangement  permits  the  bodies 
of  adjoining  vertebrae  to  embrace  each  other  in  the  dried  bones, 
and  grants  great  facility  of  motion,  in  the  living  body,  by  the 
interposition  of  the  intervertebral  substance,  as  well  as  securi- 
ty in  the  attachment  of  the  latter. 

The  oblique  processes  have  their  articular  faces  at  an  angle 
of  about  forty-five  degrees.  The  superior  face  upwards  and 
backwards,  the  inferior  downwards  and  forwards.  The  spinous 
process  is  short,  triangular,  nearly  horizontal,  and  bifurcated  at 
its  posterior  extremity,  where  it  terminates  in  two  tubercles. 
The  transverse  processes  are  short,  and  perforated  by  a  large 
canal  for  the  transmission  of  the  vertebral  artery  and  vein ;  they 
are  concave  above,  somewhat  convex  below,  and  present  two 
points  at  their  external  extremities  for  the  origin  and  insertion 
of  muscles.  The  inter- vertebral  foramen  is  formed  principally 
by  the  lower  of  the  contiguous  vertebrae. 

Of  the  Cervical  Vertebra,  individually. 

•The  first  cervical  vertebra,  commonly  called  the  Atlas,  from 
its  supporting  the  head,  presents  the  appearance  of  a  large  ir- 
regular ring,  much  thicker  at  its  sides  than  elsewhere.  It  is 
deficient  in  body,  owing  to  the  space  allotted  to  that  part  in  the 
other  vertebrae  being  occupied  by  the  processus  dentatus  of  the 
second  vertebra.  The  place  of  body  is  supplied  by  an  arch  of 
bone. 

Its  oblique  processes  are  peculiar,  both  in  shape  and  position. 
The  upper  ones  are  concave  and  horizontal,  their  long  diameters 
being  extended  from  within  outwards  and  backwards,  so  as  to 
suit  the  direction  of  the  condyles  of  the  occipital  bone  with 
which  they  articulate;  the  greatest  depth  of  their  concavity  is, 
therefore,  internal.  The  inferior  oblique  processes  are  smaller, 
slightly  concave,  and  circular;  they  rest  upon  the  shoulders  of 
the  second  vertebra.  At  the  internal  margin  of  the  oblique  pro- 


82.  SKELETON. 

cesses  a  rounded  tubercle  is  found  on  either  side  of  the  bone. 
The  transverse  ligament  of  the  neck  is  extended  between  the 
two  tubercles,  and  keeps  the  processus  dentatus  in  its  place. 

The  short  thin  bridge  at  the  fore  part  of  the  bone,  is  marked 
in  front  by  a  tubercle,  and  behind  by  an  articular  face  which 
touches  the  processus  dentatus.  The  bridge  or  section  of  the 
ring  forming  the  posterior  part  of  the  bone,  is  much  longer  and 
more  arched  than  the  anterior.  It  also  has  in  its  centre  a  tu- 
bercle, occupying  the  position  of  a  spinous  process.  At  the 
anterior  extremity  of  this  bridge,  just  behind  the  upper  oblique 
process,  there  is  a  groove,  and  sometimes  a  canal,  made  by  the 
vertebral  vessels,  just  before  they  enter  the  foramen  magnum 
oecipitis. 

The  transverse  processes  of  this  vertebra  are  at  the  sides  of 
the  thick  part  of  the  ring.  From  their  greater  length,  they  pro- 
ject considerably  beyond  the  transverse  processes  below,  and 
are  also  perforated  at  their  bases  by  the  vertebral  vessels,  which 
have  a  very  winding  course  from  them  into  the  cranium. 

The  spinal  canal  of  the  first  vertebra,  excluding  the  space  for 
the  processus  dentatus  and  transverse  ligament,  is  the  largest  in 
the  spine:  by  which  ample  provision  is  made  against  injuries  of 
the  medulla  spinalis,  notwithstanding  the  great  latitude  of  the 
rotation  of  this  bone  upon  the  second  vertebra.  A  considera- 
ble vacuity  is  left  between  the  upper  posterior  margin  of  the 
atlas  and  the  contiguous  surface  of  the  os  oecipitis,  for  the  gin- 
glymoid  motion  of  the  head  upon  the  atlas, 

The  second  vertebra  of  the  neck  is  particularly  remarkable 
for  the  elongation  of  its  body  above  into  the  processus  dentatus 
or  tooth-like  process.  This  process  rises  as  high  as  the  superior 
margin  of  the  atlas,  and  almost  touches  the  anterior  margin  of 
the  foramen  magnum  oecipitis.*  It  presents  an  articular  face 
in  front,  where  it  touches  the  first  vertebra.  It  presents  also  a 
smooth  face  behind,  W7here  it  touches  the  transverse  ligament 
Above  the  latter  face,  on  each  side,  is  a  flat  surface  for  the  ori- 
gin of  the  moderator  ligaments,  and  the  very  point  above  pre- 
sents a  small  rough  surface  for  the  vertical  ligament  going  to 
the  margin  of  the  foramen  magnum. 

*  Sometimes  it  even  forms  a  joint  with  itt 


THE   SPINE.  83 

On  each  side  of  the  tooth-like  process,  this  bone  presents  its 
superior  oblique  process,  as  a  shoulder,  nearly  horizontal,  circu- 
lar, and  somewhat  convex.  The  inferior  oblique  process  has 
nothing  peculiar  either  in  its  position  or  direction.  The  fora- 
men of  the  transverse  process  is  directed  upwards  and  outwards. 
The  interior  part  of  the  body,  like  that  of  the  other  vertebrae, 
is  cellular. 

The  posterior  part  of  the  second  vertebra  is  strong  and  broad. 
The  spinous  process  is  longer  than  any  other  except  the  seventh, 
and  sometimes  the  sixth;  it  is  also  much  larger,  is  triangular, 
presents  a  ridge  above  and  a  fossa  below,  and  is  bifurcated  at 
its  extremity.  Just  behind  the  upper  oblique  process  there  is 
a  very  superficial  notch,  scarcely  discernible,  for  the  inter- 
vertebral  foramen.  The  processus  dentatus  is  the  pivot  or  axle 
upon  which  the  head  revolves,  and  is  stationary  while  such 
motions  are  going  on. 

The  vertebrae  of  the  neck  increase  gradually  in  the  size  of 
their  bodies  from  the  second  to  the  seventh;  and  there  is  suffi- 
cient uniformity  between  them,  wth  the  exception  of  the  last, 
to  render  the  general  Inscription  applicable,  though  it  is  not 
difficult  to  observe  some  minute  and  unimportant  points  of  dif- 
ference. 

The  spinous  process  of  the  sixth  vertebra  is  long,  and  termi- 
nates in  a  sharp  point.  • 

The  seventh  cervical  looks  like  a  dorsal  vertebra,  and  has 
some  peculiarities  which  are  well  marked.  Its  body  is  larger, 
its  superior  face  is  less  concave  than  in  the  others,  and  its  infe- 
rior face  is  flat.  Its  spinous  process  is  the  longest  of  all,  is  not 
bifurcated,  but  terminates  by  a  rounded  tubercle  easily  felt  be- 
neath the  skin.  Its  transverse  processes  are  thrown  somewhat 
backwards,  and  though  there  is  a  small  foramen  in  them,  it  is 
not  large  enough  to  receive  the  vertebral  vessels.  Sometimes 
on.  the  side  of  its  body,  at  the  lower  margin,  is  a  small  face,  by 
which  it  partially  articulates  with  the  head  of  the  first  rib. 

M.  Portal*  reports,  that  in  some  rare  cases  he  has  seen  only 
six,  and  in  others,  eight  cervical  vertebrae,  with  neither  of  which 
deviations  have  1  ever  met. 

*  Anat.  Medicale.     Paris,  1803. 


84  SKELETON. 

Of  the  Dorsal  Vertebra. 

General  or  Common  Characters. — The  dorsal  vertebrae, 
amounting  to  twelve,  being  intermediate  in  position  to  those  of 
the  neck  and  loins,  are  also  intermediate  in  size.  They  diminish 
in  the  transverse  diameter  of  their  bodies  from  the  first  to  the 
third:  afterwards,  they  increase  regularly  in  size  to  the  last. 

Their  bodies  are  more  cylindroid  than  those  of  the  neck,  and 
the  most  of  them  are  marked  laterally  on  the  upper,  and  also  on 
the  lower  margins,  near  the  base  of  the  processes,  with  a  small 
articular  face,  which  receives  one-half  of  the  head  of  a  rib.  The 
adjoining  fossa  of  the  contiguous  vertebra,  receives  the  other 
half  of  the  head  of  the  same  rib.  The  superior  of  these  articu- 
lar faces  is  larger  than  the  inferior.  The  superior  oblique  pro- 
cesses are  flat,  and  present  almost  backwards;  the  inferior  are 
also  flat  and  present  as  directly  forwards.  The  transverse  pro- 
cesses are  directed  obliquely  backwards:  they  are  long,  termi- 
nate in  an  enlarged  extremity,  which  presents  an  articular  face 
in  front  for  the  tubercle  of  the  contiguous  rib.  The  transverse 
processes  as  they  descend  are  directed  more  backwards,  and  di- 
minish in  length.  The  spinal  processes  are  long,  triangular,  with 
a  broad  base,  and  an  extremity  somewhat  rough,  swollen,  and 
sharp-pointed,  except  in  the  upper  and  lower  vertebrae:  they 
have  a  ridge  above  and  a  fossa  below;  are  directed  obliquely 
downwards,  and  overlap  each  other. 

The  spinal  foramen  is  small  and  round.  The  notch  for  the 
inter-vertebral  foramen  is  formed  principally  by  the  vertebra 
above. 

Of  the  Dorsal  Vertebra — individually. 

These  vertebrae,  though  they  have  many  common  points  of 
resemblance,  yet  some  of  them  present  distinguishing  peculiari- 
ties. Of  these,  the  first  and  the  two  or  three  last,  are  the  most 
remarkable. 

The  first  has  a  complete  articular  face  on  the  side  of  its  body 
for  the  head  of  the  first  rib,  and  a  partial  surface  at  its  lower 
margin  for  the  head  of  the  second  rib.  Its  spinous  process  is 
projecting  and  not  so  oblique  as  some  of  the  others:  the  flat- 
ness of  its  body  makes  it  look  much  like  a  cervical  vertebra. 


THE  SPINE.  85 

The  three  lower  dorsal  vertebrae  approach  in  the  form  of  their 
bodies  to  those  of  the  loins.  Frequently,  but-  not  always,  the 
tenth  has  the  articular  face  for  the  head  of  the  rib,  equi- distant 
from  its  upper  and  lower  margins,  and  its  transverse  process  so 
short,  and  inclined  backwards,  that  the  tubercle  of  the  tenth  rib 
does  not  form  an  articulation  with  it.  The  eleventh  and  twelfth 
vertebras  have  also  the  fossae  for  the  heads  of  the  ribs,  in  their 
middle,  at  the  sides  of  the  roots  of  the  processes;  instead  of  a 
partial  pit  at  their  upper  and  lower  margins.  Their  transverse 
processes  are  remarkably  short,  are  directed  almost  backwards, 
and  do  not  touch  the  ribs,  and  have  therefore  no  articular  marks. 
The  spinous  process  departs  from  the  triangular  shape,  becomes 
flattened  and  vertical  at  its  sides,  is  not  far  from  being  horizon- 
tal, and  has  a  tubercle  at  its  extremity. 

The  middle  vertebrae  of  the  back  have  some  minute  points  of 
difference  among  themselves,  the  most  of  which  it  would  be 
useless  to  study.  They  increase,  as  stated,  gradually  in  size  as 
they  descend,  and  their  spinous  processes  are  very  near  to,  and 
overlap  each  other,  like  shingles  on  the  roof  of  a  house. 


Of  the  Lumbar  Vertebra. 

Common  Characters. — Their  number  has  been  stated  at  five. 
Their  bodies  are  larger  than  those  of  the  other  true  vertebrae, 
and  are  oval  on  the  upper  and  lower  surfaces,  with  the  long  di- 
ameter transverse.  The  epiphyses  at  the  margins  of  these 
faces,  are  larger  and  more  elevated.  The  spinal  foramen  is 
triangular  and  more  capacious  than  in  the  dorsal  vertebrae. 
The  inter-vertebral  notches  for  the  nerves  to  pass  out,  are  much 
larger  than  elsewhere  in  the  spine,  and  are  formed  principally 
by  the  upper  of  the  two  contiguous  vertebrae,  though  the  diffe- 
rence is  not  very  remarkable. 

The  transverse  processes  are  very  long,  and  stand  out  at  right 
angles.  The  articular  faces  of  the  upper  oblique  processes  are 
concave  and  vertical,  being  directed  very  much  inwards,  or 
looking  towards  each  other;  the  lower  oblique  processes  are 
convex,  and  have  the  articular  faces  directed  very  much  out- 
wardly. The  spinous  process  is  short,  thick,  and  horizontal; 
having  broad,  flat  sides,  and  terminating  by  an  oblong  tubercle. 

VOL.  I.— 8 


86  SKELETON. 

Of  the  Individual  Lumbar  Vertebra. 

These  bones  are  not  so  well  marked  among  themselves  as  the 
other  vertebrae.  They  may  be  distinguished  in  a  single  set,  by 
the  successive  increase  in  the  size  of  their  bodies.  The  first, 
therefore,  is  known  by  its  smallness;  by  the  comparative  short- 
ness of  its  transverse  process,  and  by  the  deep  concavity  between 
the  superior  oblique  processes. 

The  transverse  and  spinous  processes  of  the  three  middle 
vertebrae  are  rather  longer  than  those  of  the  others;  the  third 
has  them  the  longest  of  all.  The  last  lumbar  vertebra  may  be 
recognised  by  its  greater  size;  by  its  body  being  flat,  and  deeper 
in  front  than  behind,  so  as  to  give  it  somewhat  of  a  wedge  shape; 
by  the  greater  size  of  its  spinal  foramen;  by  the  obliquity  back- 
wards of  the  transverse  process;  and  by  the  wide  interval  be- 
tween the  oblique  processes,  as  well  as  by  the  lower  of  the  lat- 
ter facing  almost  directly  forwards. 


Of  the  Pelvic  Vertebrae. 

The  os  sacrum,  (sacrum,)  the  largest  by  much  of  any  of  the 
bones  in  the  spinal  column,  has  obtained  its  name  from  the  sup- 
position of  its  having  been  offered  in  sacrifice  by  the  ancients.* 
It  forms  the  posterior  and  superior  boundary  of  the  pelvis,  as 
well  as  the  pedestal  of  the  spine,  and  may  therefore  be  properly 
studied  along  with  either  of  them,  though  its  association  with 
the  spine  seems  more  natural.  In  its  lateral  boundaries  it  is  tri- 
angular: it  is  also  regularly  concave  before,  and  very  irregularly 
convex  behind. 

In  its  forming  state  this  bone  consists  of  five  pieces,  separated 
by  long  narrow  interstices  filled  with  cartilage.  It  is  in  this 
condition  that  its  pieces  bear  a  very  strong  resemblance  to  the 
true  vertebra,  and  therefore  have  obtained  the  name  of  false 
vertebrae.  They  are  all  fused  into  one  by  the  progress  and  de- 
velopment of  the  bone;  but  the  marks  of  the  original  separation 
remain,  particularly  on  its  front  surface. 

Though  the  anterior  face  of  the  sacrum  presents  generally  a 

*  Portal.  Anal.  Med.  vol.  i.  345. 


THE  SPINE.  87 

regular  concavity;  in  some  subjects,  nevertheless,  it  is  flat.  This 
surface  is  pierced  on  each  side  by  four  holes,  which  communi- 
cate with  the  spinal  cavity  and  transmit  the  anterior  nerves  of 
the  cauda  equina.  Beneath  each  range  of  holes  is  a  notch,  which 
by  the  corresponding  one  of  the*  coccyx,  is  converted  occasion- 
ally into  a  perfect  foramen  for  the  thirtieth  spinal  nerve,  or  for 
the  fifth  of  the  sacrum.  These  foramina  diminish  in  size,  from 
the  higher  to  the  lower:  their  orifices  are  funnel-shaped,  and  di- 
rected obliquely  outwards.  Horizontal  ridges  of  bone,  marking 
the  original  separation  of  the  false  vertebrae,  connect  the  holes 
of  the  two  sides. 

The  false  vertebrae  decrease  in  size  from  above,  which  is  ma- 
nifested by  the  successive  approach  of  the  foramina,  and  of  the 
horizontal  ridges.  The  first  of  them  has  almost  the  same  verti- 
cal diameter  as  the  last  of  the  loins,  besides  its  great  increase  of 
magnitude  by  the  lateral  extension  of  its  base. 

The  posterior  face  of  the  sacrum  is  very  convex  and  rough, 
and  is  equally  divided  by  its  spinous  processes.  The  processes 
belonging  to  its  three  upper  sections  or  bones,  are  for  the  most 
part  well  marked,  and  decrease  in  length  from  the  first.  The 
fourth  spinous  process  is  resolved  into  two  tubercles,  and  the 
fifth  is  fairly  separated  also  into  two  tubercles,  by  an  angular 
fissure,  with  its  base  downwards  and  open.  This  fissure,  it  may 
be  remarked,  sometimes  invades  the  fourth  spinous  process,  and 
even  the  third,  and  in  some  rare  eases  runs  the  whole  length  of 
the  posterior  surface  of  the  bone,  leaving  a  gap  from  one  end  to 
the  other.  The  upper  margin  of  the  posterior  face  of  the  sacrum 
presents  on  each  side  an  oblique  process  for  articulating  with 
the  lower  oblique  processes  of  the  last  lumbar  vertebra.  Just 
above  the  upper  spinous  process  is  a  deep  notch,  between  which, 
and  the  last  lumbar  vertebra,  is  a  very  large  vacuity,  or  gap,  ex- 
posing the  spinal  canal. 

On  each  side  of  the  spinous  processes  are  also  four  foramina, 
smaller  and  thinner  than  those  in  front,  and  for  the  passing  of 
the  posterior  nervous  cords  from  the  cauda  equina.  At  their  in- 
ternal margins  some  small  and  obscure  risings  of  bone  are  per- 
ceptible, which  may  be  considered  the  rudiments  of  oblique  pro- 
cesses. On  the  outer  side  of  these  foramina,  there  are  several 
more  strongly  marked  tubercles,  from  which  the  sacro-iliac  liga- 


88  SKELETON. 

ments  arise.  After  these  the  posterior  surface  of  the  bone  slants 
very  considerably  to  its  lateral  margin. 

The  base  of  the  sacrum  presents  in  its  middle  an  oval  surface 
for  articulating  with  the  last  lumbar  vertebra.  Between  this 
surface  and  the  oblique  process,  may  be  remarked  the  groove 
for  the  fifth  lumbar  nerve.  The  base  of  the  sacrum  continually 
thickens,  from  the  side  of  the  oval  surface  to  the  place  of  junc- 
tion with  the  ilium.  The  anterior  margin  of  this  expansion  is 
continuous  with  the  linea  ilio-pectinea;  the  posterior  margin  is 
elevated  at  its  extremity,  is  a  substitute  for  a  transverse  process, 
and  is  placed  immediately  below  the  transverse  of  the  last  lum- 
bar vertebra.  The  point  of  the  sacrum  is  truncated  where  it 
articulates  with  the  os  coccygis.  The  lateral  face  of  the  sacrum 
is  thicker  above  than  below;  its  upper  two-thirds  present  an  ir- 
regular, and  somewhat  triangular  face  for  joining  the  ilium;  the 
lower  third  is  very  thin,  and  contributes  to  form  the  sacro-scia- 
tic  notch  of  the  pelvis. 

The  spinal  canal  of  the  sacrum  is  triangular,  and  diminishes 
continually  to  its  lower  extremity,  where  it  terminates  by  a 
small  orifice,  notched  behind,  as  mentioned,  and  exposing  the 
last  piece  of  the  bone.  The  foramina  on  the  anterior  and  pos- 
terior surface  of  the  sacrum,  communicating  with  this  canal,  cor- 
respond strictly  in  their  uses  and  positions  with  the  inter-verte- 
bral foramina  of  other  parts  of  the  spine. 

The  sacrum  is  extremely  light  for  its  size,  and  its  texture  is 
in  a  high  degree  spongy;  but  its  processes  and  articular  faces 
are  quite  as  compact  as  they  are  in  other  parts  of  the  spine. 


Of  the  Coccyx  or  Caudal  Vertebra. 

The  os  coccygis  (coccyx)  resembles  the  sacrum  in  shape  and 
texture,  and  is  so  placed  as  to  continue  forwards  the  line  of  the 
curvature  of  the  sacrum.  It  consists  in  four  pieces,  sometimes 
only  three,  united  to  one  another  by  fibro-cartilaginous  matter, 
and  it  corresponds  with  the  tails  of  animals.  These  pieces  in 
the  progress  of  life,  are  not  only  anchylosed  together,  but  also 
with  the  sacrum;  so  that  all  the  false  vertebrae,  from  the  base  of 
the  sacrum  to  the  point  of  the  coccyx,  are  joined  into  a  single 
bone. 


THE   SPINE.  89 

The  upper  bone  of  the  coccyx  is  the  largest,  and  is  the  base 
of  this  little  pyramidal  pile;  it  is  united,  by  its  middle,  to  the 
truncated  apex  of  the  sacrum ;  and  its  sides,  moreover,  are,  in 
the  perfect  specimen,  elongated  several  lines  beyond  this  sur- 
face of  contact.  From  the  posterior  surface  of  the  first  bone, 
of  the  perfect  coccyx,  a  tubercle  arises  on  either  side,  which  is 
curved  upwards,  and  joins  the  bifurcated  termination  of  the  last 
spinous  process  of  the  sacrum:  between  the  two  bones  an  inter- 
vertebral  foramen  is  thus  left  for  the  passage  of  the  fifth  sa- 
cral nerve  from  the  canal  of  the  sacrum.  Immediately  below 
this  tubercle  is  a  notch,  made  by  the  sixth  sacral  nerve. 

The  remaining  bones  of  the  coccyx  are  much  smaller  than 
the  first,  and  diminish  successively.  The  surfaces  which  they 
all  present  to  each  other  are  somewhat  concave  in  the  centre. 
The  lower  end  of  the  last  bone  terminates  in  a  rough  point,  to 
which  a  cartilage  is  appended.  These  bones  are  very  spongy 
and  light:  their  principal  strength  is  derived  from  a  ligamentous 
covering.  To  them  are  attached  the  sacro-sciatic  ligaments,  the 
coccygrei,  levatores  ani,  and  the  glutaei  magni  muscles. 

SECT.  II. — DEVELOPMENT  OF  THE  VERTEBRAL  COLUMN, 

This  column  is  much  longer,  in  proportion  to  the  limbs,  at 
birth,  than  it  is  in  adult  life,  and  upon  it  depends  the  principal 
length  of  the  individual  at  this  period.  The  head  is  always  in 
proportion  to  the  length  of  the  spine.  This  predominance  in 
the  head  and  spine  is,,  no  doubt,  connected  with  the  necessity 
of  an  early  development  in  the  nervous,  respiratory,  and  ali- 
mentary systems,  in  order  to  maintain  the  life  of  the  individual; 
whereas,  the  use  of  the  upper  and  lower  extremities  being  called 
for  only  at  a  more  advanced  period,  their  development  is  not 
in  proportion.  It  is  remarked,  that  in  adult  life  the  principal 
difference  in  the  stature  of  individuals  depends  upon  the  length 
of  the  lower  extremities;  (he  trunk,  including  the  head,  being 
of  nearly  the  same  length  in  all.  This  rule,  however,  like  most 
others,  has  numerous  exceptions.  The  spinal  canal  and  the  inter- 
vertebral  foramina  are,  also,  proportionably  larger  in  the  foetus. 

The  spine  of  the  foetus  is  but  badly  suited  to  the  purposes  of 
standing  and  walking.  Its  spinous  processes  are  deficient,  in 
consequence  of  which,  the  muscles  which  are  intended  to  keep 

8* 


90  SKELETON 

it  erect,  have  their  insertion  so  much  in  the  line  of  motion,  that 
they  perform  their  part  very  imperfectly,  and  the  spine  is  con- 
tinually bending  forwards,  from  the  erect  position.  All  the 
transverse  processes  are  also  imperfectly  developed,  those  of 
the  loins  are  particularly  deficient;  those  of  the  thorax  and  neck 
are  less  deficient;  as  in  the  one  case  they  have  to  form  an  arti- 
cular surface  for  the  ribs,  and  in  the  other  to  allow  passage  to 
the  vertebral  artery.  The  bodies  of  the  vertebrae  are.  imper- 
fectly ossified,  and  are  separated  by  cartilage  from  the  processes. 
The  epiphyses,  or  upper  and  lower  surfaces  of  the  bodies,  are 
in  the  state  of  cartilage:  the  bodies,  therefore,  are  rounded  both 
above  and  below,  whereby  their  surfaces  of  contact  are  much 
reduced  in  extent,  and  the  line  of  support  to  the  trunk  rendered 
much  less  firm.  When,  at  this  age,  the  vertebras  are  macerated, 
their  bodies  present  themselves  as  small  rounded  tubercles;  and 
very  nearly  one-half  the  whole  length  of  the  spine  is  made  up 
of  the  cartilaginous  epiphyses  and  the  inter-vertebral  cartilages- 
The  spine,  in  the  foetus,  is  almost  straight,  and  scarcely  presents 
at  all  those  curvatures,  for  which  it  is  so  remarkable  in  adult 
life.  This  depends  upon  the  rounded  form  of  the  bodies  of  the 
vertebra3,  and  the  sameness  of  thickness  in  the  inter-vertebral 
matter  at  its  anterior  and  posterior  edge. 

SECT.  III.— ON  THE  USES  OF  THE  VERTEBRAL  COLUMN.. 

The  vertebral  column  performs  three  important  offices  in  the 
animal  economy.  It  affords  a  secure  lodgement  to  the  spinal 
marrow;  is  a  line  of  support  to  the  trunk,  in  every  variety  of 
position;'and  is  the  centre  of  all  its  movements. 

In  standing,  the  spine  also  supports  the  head,  which  it  can 
do  very  conveniently,  from  the  horizontal  direction  of  the  con- 
dyles  and  their  nearly  central  position  on  the  occiput,  and  from 
the  head  being  almost  in  equilibrium  when  we  stand  erect.  The 
volume  of  the  head  is  so  much  greater  before  the  condyles  than 
behind  them,  that  upon  a  superficial  view  one  would  suppose  its 
preponderance  in  front  to  be  very  considerable.  This  is,  how- 
ever, less  than  it  might  seem  to  be,  for  two  reasons:  one  is,  that 
the  diameters  of  the  head  are  augmented  behind  the  condyles, 
and,  secondly,  it  is  formed  of  solid  matter;  whereas,  in  front 
a  great  deal  of  it  is  hollow,  for  the  construction  of  the  nose  and 


VERTEBRAL  COLUMN.  91 

the  sinuses  bordering  upon  it.  The  head,  though  nearly  ba- 
lanced, has  some  preponderance  in  front,  which  is  manifested 
by  its  falling  forwards  whenever  we  sleep  in  the  erect  position, 
or  when  the  sudden  suspension  of  life  destroys  the  contraction 
of  the  muscles  on  the  back  of  the  neck. 

In  the  lower  orders  of  animals,  the  obliquity  of  the  condyles, 
their  situation  at  one  end  of  the  head,  and  the  great  length  of 
the  face,  acting  as  a  weight  upon  a  long  lever,  have  a  continual 
tendency  to  incline  the  head  downwards ;  which  is  only  par- 
tially counteracted  by  the  largeness  of  the  muscles  and  liga- 
ments on  the  back  of  the  neck. 

The  horizontal  direction  of  the  condyles,  and  their  location 
near  the  centre  of  the  base  of  the  head,  have  arrested  the  atten- 
tion of  naturalists,  and  established  for  man  characters  distin- 
guishing him,  from  all  other  animals,  for  facility  in  maintaining 
the  erect  attitude.  Bichat  happily  observes,  that  from  this  con- 
formation result  the  following  peculiarities  in  his  organization : 

1.  Less  strength  in  the  muscles  of  the  neck  than  in  quadrupeds; 

2.  Less  projection  in  the  occipital  bone,  where  the  muscles  are 
inserted ;  and,  3.  An  imperfect  development  of  the  ligamentum 
nuchae. 

The  thoracic  and  abdominal  viscera,  by  being  placed  in  front 
of  the  spine,  and  having  no  counterpoise  behind,  have  a  conti- 
nued tendency  to  bend  it.  This  is  only  resisted  by  the  mus- 
cles which  fill  up  the  long  gutter  on  either  side  of  the  spinous 
processes,  and  are  inserted  into  the  ribs,  the  spinous  and  the 
transverse  processes.  The  lumbar  vertebrae  and  the  appertain- 
ing muscles  and  ligaments,  having  an  increased  duty  to  per- 
form, from  the  lowness  of  their  position,  and  the  variety  of  their 
movements,  become  the  soonest  affecteM  by  fatigue  and  bodily 
weakness;  and  therefore  manifest  sooner  the' sensation  of  las- 
situde, notwithstanding  the  augmented  volume  of  the  bodies 
and  processes  of  the  vertebra),  and  of  the  muscular  masses  in- 
serted into  them. 

The  mechanical  arrangement  of  the  spine  permits  it  to  per- 
form the  motions  of  flexion,  extension,  lateral  bending,  circum- 
duction,  and  rotation. 

1.  Flexion,  or  that  posture  in  which  the  spine  is  bent  for- 
wards, is  the  most  extensive  of  its  movements  :  the  general  me- 


92  SKELETON. 

chanism  of  the  human  body  disposes  us  to  approach  surround- 
ing objects  in  that  direction;  and  the  musdes  of  the  abdomen, 
besides  their  intrinsic  strength,  act  most  advantageously  in  pro- 
ducing it,  by  being  removed  to  a  great  distance  from  the  centre 
or  line  of  motion.  In  this  position  the  inter-vertebral  carti- 
lages are  diminished  or  compressed  in  front,  and  thickened  be- 
hind, the  anterior  vertebral  ligament  is  in  a  state  of  relaxation, 
while  the  posterior  vertebral  ligament  and  those  which  connect 
the  spinous  processes  are  in  a  state  of  proportionate  tension. 

2.  The  motion  of  extension,  on  the  contrary,  is  much  more 
limited  from  several  causes.     The  muscles  which  act  in  this 
case,  by  arising  either  from  the  posterior  face  of  the  pelvis,  or 
from  the  transverse  processes,  and  going  upwards  to  be  insert- 
ed either  into  the  ribs,  the  transverse  or  the  spinous  processes, 
are  much  less  advantageously  placed  than  the  abdominal  mus- 
cles, in  regard  to  the  length  of  the  lever  which  they  employ. 
Moreover,  mechanical  obstruction  is  opposed  to  this  motion  by 
the  spinous  processes  of  the  back  and  neck,  being  very  near  to, 
and  overlapping  each  other.     The  abdominal  muscles  also  af- 
ford a  strong  resistance  to  its  being  carried  beyond  a  certain 
point  as  any  one  may  assure  himself  of,  by  the  tension  commu- 
nicated to  these  muscles  from  placing  a  large  billet  of  wood  un- 
der the  loins  of  a  subject;  and,  when  they  are  cut  through  tran- 
versely,  the  immediate  consequence  is,  a  great  increase  in  the 
posterior  flexion  of  the  spine,  through  the  agency  of  the  lower 
dorsal  and  the  lumbar  vertebras.     The  anterior  vertebral  and 
the  inter-vertebral  ligaments,  likewise,  oppose  the  extension  of 
the  spine,  much  more  than  the  elastic  and  the  inter-spinous  li- 
gaments do  its  flexion.* 

3.  The  lateral  inclination  of  the  spine  is  a  motion  of  consi- 
derable extent,  and  is  obtained  both  by  the  very  advantageous 
position  of  the  muscles  on  the  side  of  the  trunk  and  neck,  and 
by  the  little  mechanical  resistance  to  it  from  the  shape  and  ar- 
rangement of  the  parts  concerned.     A  principal  impediment  to 
this  motion  being  carried  beyond  a*  certain  point,  is  presented 
by  the  ribs  striking  against  each  other.     The  transverse  pro- 
cesses of  all  the  vertebrae  are  so  far  apart,  particularly  in  the 
loins,  that  they  scarcely  deserve  to  enter  into  the  estimate  of 


VERTEBRAL  COLUMN.  93 

resistances.  As  the  muscles  of  the  one  side  produce  the  late- 
ral curvature,  so  their  resistance  on  the  other  limit  it  to  a  cer- 
tain extent,  as  may  be  readily  ascertained  by  cutting  them 
through. 

4.  The  circumduction  of  the  spine  is  that  motion  in  which 
the  trunk  is  caused  to   describe  a  cone,  the  base  of  which  is 
above,  and  the  apex  below.     It  is  performed  on  the  lower  dor- 
sal and  the  lumbar  vertebrae,  and  is  a  succession  of  the  move- 
ments already  described. 

5.  The  rotation  of  the  spine  is  a  very  limited  motion.     It  is 
performed  almost  entirely  on  the  lower  dorsal  and  the  upper 
lumbar  vertebrae,  and  presents  in  its  analysis  a  series  of  minute 
and  oblique  slidings  of  the  body  of  one  vertebra  upon  another, 
the  pivot  being  the  oblique  processes.     The  action  occurs  by 
the  lateral  yielding  of  the  inter-vertebral  substance;  it  must, 
therefore,  be  almost  inconceivably  small  in  any  individual  sub- 
stance, particularly  when  the  latter  has  been  hardened  and  ren- 
dered more  fibrous  by  old  age.     In  the  very  young  subject  it 
is  more  appreciable. 

Of  the  Motions  peculiar  to  each  Class  of  Vertebra. 

1.  The  cervical  vertebrae,  as  a  whole,  enjoy  a  considerable 
share  of  flexion,  extension,  lateral  inclination:  and  of  circumduc- 
tion, as  the  result  of  the  other  motions.  Their  rotation,  or  the 
oblique  sliding  of  one  vertebra  upon  the  other,  is  very  limited. 
The  apparent  facility  with  which  they  are  twisted  upon  each 
other,  when  the  face  is  turned  to  the  shoulders  alternately,  is 
almost  wholly  the  motion  of  the  first  vertebra  upon  the  second, 
the  participation  of  the  other  vertebrae  being  very  inconsidera- 
ble. The  possibility  of  the  dislocation  of  these  vertebrae,  with 
the  exception  of  the  first,  is  very  stoutly  denied  by  authorities 
of  the  first  standing  in  anatomy,  on  the  score  that  too  great  a 
resistance  to  this  accident  is  afforded  by  the  inter-vertebral  and 
yellow  ligaments,  by  the  inter-spinal  and  inter- transverse  mus- 
cles, by  the  inter-locking  of  the  bodies  of  the  vertebrae  through 
their  reciprocal  concavities  and  convexities,  and  by  the  shape 
and  extent  of  their  oblique  processes. 


94  SKELETON. 

Some  years  ago,  I  met  with  a  case  in  which  there  was  every 
reason  to  believe  that  a  partial  displacement  or  dislocation  had 
occurred  about  the  fourth  vertebra,  in  a  boy  of  eight  or  ten  years. 
It  rose  from  his  struggling  to  extricate  himself  from  the  grasp 
of  a  school-mate,  who  held  him  near  the  ground  by  the  back  of 
the  head,  with  the  spine  bent  forwards.  This  position,  it  is 
evident,  was  calculated  to  lift  the  oblique  processes  of  the  verte- 
brae over  each  other;  and  an  oblique  force  applied  at  the  same  time 
consummated  the  accident,  by  twirling  the  lower  oblique  process 
over  the  upper  margin,  and  in  front  of  the  one  with  which  it 
was  articulated  below.  The  displacement  was  manifested  by 
inability  to  move  the  neck;  by  a  permanent  inclination  and  turn 
of  the  head  to  the  side  opposed  to  the  injured  one;  and  by  an 
inequality  in  the  range  of  the  anterior  points  of  the  transverse 
processes  of  the  side  affected.  I  succeeded  in  replacing  the  bone 
by  lifting  its  dislocated  side  over  the  lower  oblique  process, 
communicating  at  the  same  moment  a  rotatory  motion,  the  re- 
verse of  that  by  which  the  accident  had  happened.  In  an  in- 
stant, the  patient  was  relieved;  from  extreme  pain,  fixed  defor- 
mity, and  inability  to  move  the  neck,  he  performed  with  freedom 
all  the  motions  natural  to  the  part. 

The  principal  motions  of  the  head  upon  the  first  vertebra  are 
those  of  flexion  and  extension:  the  power  of  the  condyles  to 
slide  horizontally  from  one  side  to  the  other  in  the  cavities 
formed  in  the  atlas,  is  excessively  restricted,  both  by  the  shape 
of  the  proximate  articular  surfaces,  and  by  the  arrangement  of 
the  ligaments:  this  motion  is,  in  fact,  so  inconsiderable  as  scarce- 
ly to  deserve  notice.  Even  flexion  and  extension  appear  greater 
than  they  actually  are,  in  consequence  of  the  lower  vertebrae 
most  commonly  concurring  in  these  motions.  When  simply 
the  head  is  flexed  upon  the  atlas,  while  the  other  vertebrae  are 
kept  erect,  the  chin  approaches  the  sternum,  and  the  skin  of  the 
neck  is  thrown  into  folds;  but  when  all  the  bones  are  flexed, 
the  head  is  thrown  forwards  and  the  skin  is  kept  tense.  The 
flexion  of  the  head  upon  the  atlas  is  restricted  by  the  ligamen- 
tum  nuchae,  and  by  the  ligament  passing  from  the  posterior 
margin  of  the  occipital  foramen  to  the  posterior  bridge  of  the 
atlas.  The  extension  of  the  head  is  restricted  by  the  vertical, 
moderator,  and  anterior  vertebral  ligaments. 

The  motion  of  the  atlas  upon  the  axis  is  limited  strictly  to 


VERTEBRAL  COLUMN.  95 

rotation.     The  confinement  of  the  processus  dentatus  by  the 
transverse  ligament  behind,  and  by  the  anterior  bridge  of  the 
first  vertebra  in  front,  prevents  thoroughly  both  flexion  and  ex- 
tension.    The  horizontal  direction  and  the  flatness  of  the  cor- 
responding articular  faces  of  these  two  vertebrae,  also  prevent 
any  lateral  inclination.     In  compensation  for  these  restrictions, 
the  rotatory  motion  is  enjoyed  to   great  extent,  and  is  amply 
provided  for,  by  the  extreme  looseness  and  thinness  of  the  cap- 
sular  ligament  of  the  oblique  processes.     In  this  motion  the  arch 
of  the  atlas  and  the  transverse  ligament  rotate  on  the  tooth-like 
process  to  the  right  and  left  alternately;  at  the  same  time  the 
inferior  oblique  process  of  the  atlas  is  slid  either  forwards  or 
backwards,  according  to  the  general  movement  upon  the  upper 
oblique  process  of  the  dentata.     This  movement  is  checked,  at 
a  certain  point,  by  the  moderator  ligaments,  which,  by  the  close 
connexion  of  the  head  and  first  vertebra,  answer  the  same  pur- 
pose as  if  they  were  inserted  into  the  latter.     It  is  also  checked 
by  the  capsular  ligament,  notwithstanding  the  general  laxity  of 
the  latter.     But  still  it  is  not  difficult  for  it  to  exceed  its  natu- 
ral bounds,  and  for  the  oblique  process  of  the  atlas  to  pass  com- 
pletely beyond  the  margin  of  that  of  the  dentata,  and  in  return- 
ing to  lock  against  it.     This,  in  fact,  happens,  in  the  great  majo- 
rity of  instances,  where  violence  from  falls,  and  so  on,  has  been 
applied  to  the  body,  and  results  in  injury  to  the  neck,  particularly; 
and  when,  in  the  abrupt  turning  of  the  head,  produced  by  the 
action  of  the  muscles,  the  individual  finds  himself  incapable  of 
bringing  it  back.     This  articulation  is,  unquestionably,  less  pro- 
tected, and   more  exposed  to   accident,  than  any  other  in   the 
spine;  and,  as  just  stated,  is  therefore  supposed,  by  some,  to  be 
the  only  one  in  the  neck  admitting  of  luxation. 

Most  frequently,  in  this  luxation,  when  it  is  produced  by  ex- 
ternal violence,  death  is  the  immediate  result,  from  the  spinal 
marrow  being  pressed  upon  and  disorganized  above  the  origin 
of  the  phrenic  nerve.  The  seat  of  the  principle  of  respiration 
is  in  the  medulla  oblongata,  and  its  agents  are  the  phrenic  and 
the  intercostal  nerves;  the  communication  with  which  being 
thus  cut  off,  respiration,  and  consequently  circulation,  stop  im- 
mediately. Bichat  thinks,  that,  when  death  is  thus  suddenly 
produced,  the  processus  dentatus,  by  rupturing  its  own  ligaments 
connecting  it  to  the  occiput,  slides  by  the  falling  of  the  head 


96  SKELETON. 

forwards,  beneath  the  transverse  ligament,  and  presses  upon  the 
spinal  marrow.  On  the  contrary,  when  it  is  a  simple  displace- 
ment of  the  oblique  processes,  as  the  odontoid  process  remains 
within  its  boundaries,  and  its  ligaments  are  only  stretched,  there 
is  no  danger  of  death.  Fatal  accidents  have  happened  to  this 
articulation,  by  holding  an  infant  from  the  ground,  by  the  two 
hands  applied  to  the  head,  from  his  struggles  to  disengage  him- 
self. A  posture-maker  is  said  to  have  died  on  the  spot,  from 
communicating  a  rotatory  motion  to  his  trunk,  while  its  weight 
was  sustained  by  inverting  his  head,  and  making  the  latter  the 
base  of  support.  When  the  vertebras  are  displaced  in  such  per- 
sons, as  well  as  in  those  hung  by  the  neck,  it  is  supposed  that 
this  sliding  of  the  processus  dentatus  from  beneath  the  trans- 
verse ligament  takes  place;  as,  by  experiments  on  the  dead 
body,  it  is  found  that  such  displacement  occurs  much  more  rea- 
dily than  the  rupture  of  the  transverse  ligament. 

2.  The  dorsal  vertebrae  are  capable  of  but  very  little  motion 
in  any  direction.     The  rigidity  and  length  of  the  sternum  pre- 
vent them  from  flexion,  the  overlapping  and  obliquity  of  their 
spinous  processes  prevent  them  from  extension,  and  the  ribs  pre- 
vent them  from  lateral  inclinations.     It  is,  however,  to  be  ob- 
served, that  as  those  obstacles  are  diminished,  successively,  in 
the  five  lower  dorsal  vertebrae,  consequently  they  become  more 
and  more  capable  of  motion  upon  each  other.     Luxation  among 
them,  at  any  point,  is  thought  to  be  impossible,  from  the  strength 
of  their  ligamentous  attachments,  and  from  the  arrangement  of 
their  articular  faces. 

3.  The  lumbar  vertebrae  move  with  great  comparative  free- 
dom upon  one  another;  admitting,  as  stated,  of  flexion,  exten- 
sion, and   lateral  inclination.     Below,  however,  they  are  much 
more  restrained  than  they  are  above;  hence,  it  results,  that  the 
principal  seat  of  the  motions   of  the   trunk  upon  the  spine,  is 
about  the  connexion  of  the  lumbar  and  dorsal  vertebrae.     Dis- 
location   is    here,    also,   thought    to    be    impossible,    from   the 
strength  of  their  ligamentous  attachments,  from  the  great  dia- 
meters of  their  bodies,  and  from   the  deep  interlocking  of  the 
oblique  processes. 


OSSA  INNOMINATA.  97 


SECT.  IV.  -  OF  THE  OSSA  INNOMINATA. 

(Os  Cozauz,  ou  des  Isles.)—  These  bones,  two  in  number,  are 
situated  one  at  either  side  of  the  sacrum,  and  constitute  the  la- 
teral and  anterior  parietes  of  the  pelvis;  forming,  along  with  the 
sacrum  and  coccyx,  the  whole  of  this  latter  cavity. 

The  os  innominatum,  from  having  been,  in  its  original  state, 
in  three  pieces,  notwithstanding  they  subsequently  coalesce  firm- 
ly in  the  adult,  and  preserve  scarcely  any  vestige  of  their  pri- 
mitive distinction,  is  divided  by  anatomists  into  ilium,  ischium, 
and  pubes. 


Os  lliumj  (Ilion.)  —  This,  the  largest  of  the  three  portions, 
forms  all  the  upper  rounded  part  of  the  os  innominatum,  and  is 
the  haunch  bone  of  common  language.  Its  superior  margin  is 
a  semicircle,  rather  thicker  towards  the  extremities  than  in  the 
middle.  The  inequality,  when  viewed  from  above,  is  very  ap- 
parent, as  well  as  a  slight  curvature  resembling  the  letter  S. 
This  margin  of  the  bone  is  called  its  crest  or  spine,  presents  an 
internal  lip  for  the  origin  of  the  transversalis  abdominis  muscle, 
an  external  one  for  the  insertion  of  the  obliquus  externus,  and 
an  intermediate  edge  for  the  origin  of  the  obliquus  internus. 
The  anterior  extremity  of  the  spine  is  terminated  by  a  project- 
ing point,  called  the  anterior  superior  spinous  process,  from 
which  arise  the  tensor  vaginas  femoris,  the  sartorius,  and  the 
beginning  of  Poupart's  ligament.  The  posterior  extremity  of 
the  crest  is  also  projecting  and  pointed,  but  less  so  than  the 
other,  and  obtains  the  appellation  of  the  posterior  superior  spi- 
nous process. 

The  anterior  margin  of  the  os  ilium  is  unequal,  and  divided 
into  two  portions,  of  nearly  the  same  length,  by  a  strong,  well- 
marked  projection,  the  anterior  inferior  spinous  process,  which 
is  placed  an  inch  and  a  half  below  the  anterior  superior,  and 
gives  origin  to  the  rectus  femoris.  This  margin  joins  with  the 
pubes  by  a  large  flattened  elevation,  called  the  ilio  pectineal  pro- 
tuberance. Between  the  latter  and  the  anterior  inferior  spinous 
process,  a  concavity  exists  which  is  occupied  by  the  junction  of 
the  psoas  magnus  and  iliacus  internus  muscles,  where  they  pass 
under  Poupart's  ligament.  Between  the  two  anterior  spinous 

VOL.  L—  9 


98  SKELETON. 

processes  is  another  concavity,  from  which  the  anterior  edge  of 
the  gluteus  medius  arises. 

The  posterior  margin  of  the  ilium  is  also  very  unequal,  both 
in  its  direction  and  thickness.  The  posterior  inferior  spinous 
process  is  about  sixteen  lines  below  the  posterior  superior,  and 
terminates  a  cutting  edge  running  between  these  two  processes. 
Just  below  it  we  find  the  d*eep  excavation  called  the  sciatic 
notch,  through  which  pass  out  the  pyriform  muscle,  the  sciatic 
nerve,  and  several  blood  vessels. 

The  exterior  face  of  the  ilium,  called  its  dorsum,  is  generally 
convex  and  rounded;  its  margins,  however,  are  so  elevated,  that 
partial  depressions,  or  sinkings  below  the  general  surface,  may 
be  remarked,  especially  at  its  back  part.  Just  above  the  two 
posterior  spinous  processes,  a  flatness  is  observable,  from  which 
a  part  of  the  gluteus  magnus  arises.  A  semicircular  rough 
ridge  begins  at  or  near  the  anterior  superior  spinous  process, 
and  may  be  traced  on  this  surface  of  the  bone  to  the  sciatic 
notch.  All  that  portion  of  the  dorsum  between  this  ridge  and 
the  spine,  with  the  exception  of  the  little  flat  surface  just  above 
the  posterior  spinous  processes,  gives  origin  to  the  gluteus  me- 
dius. The  dorsum  terminates  below  at  the  acetabulum,  and  be- 
tween the  latter  and  the  semicircular  ridge  is  the  surface  for  the 
origin  of  the  gluteus  minimus. 

The  internal  face  of  the  ilium,  or  that  which  looks  towards 
the  belly,  is  called  its  costa  or  venter.  Its  superior  part,  amount- 
ing to  about  two-thirds  of  the  whole  surface,  is  very  concave, 
and  is  the  iliac  fossa,  which  is  occupied  by  the  iliacus  internus 
muscle.  The  fossa  is  continued  forwards  into  the  hollow  below 
the  anterior  inferior  spinous  process,  and  over  the  acetabulum. 
The  iliac  fossa  is  terminated  below  by  a  rounded  ridge,  a  part  of 
the  linea  ilio-pectinea  that  separates  the  greater  from  the  lesser 
pelvis.  The  remaining  third  of  the  costa  of  the  ilium  is  very 
rough  and  unequal,  and  is  appropriated  to  the  articulation  with 
the  sacrum,  and  to  the  origin  of  some  of  the  muscles  of  the  back. 
Immediately  posterior  to  the  sciatic  notch  is  the  surface  for  the 
sacrum,  which  is  somewhat  triangular,  but  irregularly  so,  and 
extends  from  the  iliac  fossa  to  the  posterior  inferior  spinous 
process.  Behind  the  sacral  surface  is  another,  twice  as  large, 
strongly  marked  by  its  roughness,  and  elevated  into  a  vertical 
ridge  at  its  middle.  Anterior  to  this  ridge  arise  many  of  the 


OSSA  INNOMINATA.  99 

ligamentous  fibres,  fastening  the  ilium  to  the  sacrum;  but  pos- 
terior to  it  is  the  surface  of  origin  to  the  multifidus  spinae,  and 
the  sacro-lumbalis  muscles. 

Os  Pubis,  (Pubis.) — This  bone  constitutes  the  fore  part  of 
the  innominatum,  and  is  much  the  smallest  of  the  three.  It  is 
composed  by  a  body  and  two  large  branches  from  it,  one  run- 
ning downwards  to  join  the  ischium,  and  the  other  backwards 
and  upwards  to  join  the  ilium. 

The  body  of  the  pubes  is  joined  to  its  fellow  on  the  opposite 
side  by  a  flat  surface,  called  the  symphysis,  which  is  eighteen 
or  twenty  lines  in  its  long  diameter.  The  superior  part  of  the 
body  also  presents  a  flat  surface,  called  its  horizontal  portion, 
which  is  bounded  outwardly  by  the  spinous  process  about  an 
inch  from  the  symphysis.  The  horizontal  portion  and  the  sym- 
physis form  a  right  angle.  From  the  exterior  face  of  the  spine 
two  ridges  proceed  outwardly;  the  posterior  is  the  crista;  it  is 
sharp,  elevated,  and  makes  the  anterior  half  of  the  linea  ilio- 
pectinea;  the  anterior  ridge  is  lower  down,  increases  in  its 
elevation  as  it  goes  along,  is  rounded,  and  runs  nearly  horizon- 
tally to  terminate  in  the  anterior  upper  margin  of  the  acetabu- 
lum.  Between  the  two  ridges  is  a  superficial  triangular  con- 
cavity occupied  by  the  origin  of  the  pectineus  muscle;  the  base 
of  the  triangle  is  bounded  by  the  protuberance  formed  at  the 
junction  of  the  pubes  and  ilium,  and  it  is  exactly  over  this 
part  that  the  femoral  vessels  pass;  its  apex  is  the  spine  or  spi- 
nous process  of  the  pubes.  The  extremity  of  the  upper  branch 
of  the  pubes  is  triangular,  and  much  enlarged  where  it  contri- 
butes to  the  acetabulum. 

The  inferior  branch  of  the  pubes,  technically  called  its 
ramus,  is  a  flattened  process  about  an  inch  in  length,  and,  as 
mentioned,  descends  to  join  the  ischium.  Its  exterior  is  plain, 
and  has  no  mark  deserving  of  attention ;  but  the  internal  face, 
near  the  anterior  margin,  is  concave  for  attaching  the  crus  of 
the  penis  or  of  the  clitoris. 

The  body  of  the  pubes  in  front  is  concave,  and  gives  origin 
to  the  adductor  longus  and  brevis  muscles;  behind,  it  is  only 
sufficiently  concave  to  participate  in  the  general  concavity  of 
the  pelvis. 


100  SKELETON. 

Os  Ischium,  (Ischion.) — This  bone  forms  the  posterior  infe- 
rior portion  of  the  os  innominatum,  and  is  the  next  in  size  to 
the  ilium.  It  is  of  a  triangular  form,  and  has  the  anterior 
extremity  bent  upwards  to  join  with  the  pubes.  The  latter 
part  is  its  crus  or  rarnus,  and  the  remainder  is  its  body. 

The  body  of  the  ischium  is  a  triangular  pyramid,  the  inter- 
nal side  of  which  is  smooth  and  uniform,  but  the  posterior  and 
the  external  sides  are  very  unequal.  The  internal  side  is  broad 
above  and  narrow  below ;  at  the  middle  of  its  posterior  margin 
is  the  spinous  process,  a  projection  of  considerable  magnitude, 
and  sharp-pointed,  for  attaching  the  lesser  sacro-sciatic  liga- 
ment. Immediately  below  the  spinous  process  is  a  smooth 
concave  surface,  forming  a  trochlea,  over  which  the  obturator 
interims  muscle  plays.  Below  this  trochlea,  and  forming  the 
most  inferior  internal  margin  of  the  bone,  is  a  long  ridge, 
somewhat  more  elevated  behind  than  in  front,  into  which  the 
great  sacro-sciatic  ligament  is  inserted.  The  internal  face  of 
the  ischium,  though  technically  called  its  plane,  departs  from 
the  perfect  regularity  implied  in  that  name,  by  participating  in 
the  general  concavity  of  the  pelvis. 

The  posterior  face  of  the  ischium  is  swollen  out,  above,  into 
a  rounded  surface,  for  the  strengthening  the  posterior  parietes 
of  the  acetabulum.  This  swell  is  bounded,  below,  by  a  trans- 
verse depression  or  fossa;  immediately  below  which,  is  the 
tuberosity  of  the  ischium,  a  large  rough  surface  extending 
from  the  fossa  to  the  beginning  of  the  crus.  This  rough  sur- 
face is  subdivided  into  four,  two  above,  and  two  below.  The 
one  above,  which  is  external,  and  nearest  to  the  acetabulum, 
gives  origin  to  the  semi-membranosus  muscle;  the  other, 
which  is  internal,  gives  origin  to  the  semi-tendinosus,  and  to 
the  long  head  of  the  biceps  flexor  cruris.  Of  the  two  flat  sur- 
faces below,  the  one  which  borders  on  the  ridge  for  the  inser- 
tion of  the  great  sacro-sciatic  ligament,  is  the  part  on  which 
we  sit,  and  the  last  surface,  which  is  exterior  again  to  this, 
gives  origin  to  a  part  of  the  adductor  magnus  muscle. 

The  exterior  face  of  the  ischium,  above,  forms  the  lower  part 
of  the  acetabulum,  and  is,  therefore,  very  much  excavated; 
below  this  the  surface  is  flat,  and  sufficiently  uniform  to  dis- 
pense with  a  particular  description. 

The  crus  of  the  ischium  is  flattened  internally  and  externally, 


OSS  A  1NNOMINATA.  101 

and  in  the  adult  it  is  fused  completely  into  the  crus  of  the 
pubes,  so  that  very  faint  marks  of  their  primitive  separation 
are  left.  The  anterior  margin  of  the  crus  has,  for  the  origin 
of  the  crus  penis  and  the  erector  penis  muscle,  an  excavation 
continuous  with  that  on  the  crus  of  the  pubes. 

In  examining  the  general  features  of  the  os  innominatum,  it 
will  be  observed,  that  its  outline  is  in  some  degree  like  the 
figure  8;  the  narrowing  in  its  centre  being  produced  by  the 
sciatic  notch  below,  and  by  the  deep  concavity  above,  between 
the  anterior  superior  spinous  process  and  the  symphysis  of  the 
pubes.  The  regularly  rounded  margin  of  the  ilium  above,  and 
of  the  ischium  below,  contribute  to  the  resemblance,  but  the 
angle  of  the  pu-bes  interrupts  it.  The  narrowest  part  of  the 
bone,  or  its  neck,  is  between  the  top  of  the  sciatic  notch  and 
the  fossa  below  the  anterior  inferior  spinous  process.  It  will 
also  be  remarked,  that  the  posterior  margin  of  the  sciatic  notch 
is  formed  by  the  ilium,  and  the  anterior  by  the  ischium. 

The  acetabulurn,  or  the  cotyloid  cavity,  (camli  cotyloide,)  is 
placed  immediately  on  the  outside  of  the  neck  of  the  os  inno- 
minatum. In  infancy  one-fifth  of  it  is  seen  to  be  made  by  the 
pubes,  two-fifths  by  the  ilium,  and  two-fifths  by  the  ischium. 
It  is  a  very  deep  hemispherical  depression,  having  a  sharp  ele- 
vated margin  all  around,  particularly  at  its  superior  part. 
The  inferior  margin,  amounting  to  one-eighth  of  the  whole 
circumference,  is  comparatively  shallow,  and  is,  indeed,  con- 
verted into  a  notch,  sunk  much  below  the  general  surface  of 
the  brim.  The  greater  part  of  the  acctabulum  is  smooth,  and 
incrusted  with  cartilage  wherever  the  head  of  the  os  femoris 
is  applied  to  the  support  of  the  trunk;  but  the  very  bottom, 
with  the  intervening  surface  continuous  with  the  notch, 
amounting  to  rather  more  than  one-fourth  of  the  whole  cavity, 
is  rough,  sunk  below  the  general  concavity,  and  is  occupied 
by  a  soft  vascular  fat. 

In  the  fore  part  of  the  innominatum  a  large  deficiency,  called 
the  thyroid  foramen,  (foramen  thyroideum,)  exists  between  the 
pubes  and  ischium.  In  the  male  subject  it  is  triangular,  with 
the  angles  rounded  ;  but  in  the  female  it  is  rather  oval.  Lead- 
ing from  the  plane  of  the  ischium  is  a  groove,  which  goes 
along  the  superior  end  of  the  foramen,  and  appears  externally 

9* 


102  SKELETON. 

under  the  anterior  ridge  of  the  pubes.     It  conducts  the  obtura- 
tor vessels  and  nerve  to  the  inner  side  of  the  thigh. 

The  texture  of  the  os  innominatum  is  cellular  internally, 
with  a  condensed  lamella  externally.  It  is  of  very  various 
thickness.  The  ilium,  in  its  centre,  has  the  external  and 
internal  sides  so  near  one  another,  that  in  most  adults  the  light 
will  shine  through  it.  A  large  foramen  is  seen  on  the  venter 
of  the  ilium,  and  another  on  its  dorsum,  for  the  transmission  of 
nutritious  arteries.  There  are  several  others,  smaller,  at  va- 
rious points  of  the  os  innominatum,  for  the  same  purpose,  and 
for  the  adhesion  of  ligamentous  fibres. 


SECT.  V. — OF  THE  PELVIS,  GENERALLY. 

The  sacrum  and  coccyx  behind,  and  the  ossa  innominata  at 
the  sides  and  in  front,  constitute,  as  observed,  the  whole  cavity 
called  pelvis,  (bassin.)  Its  position  is  such,  that,  in  the  adult, 
it  divides  the  entire  length  of  the  body  into  two  parts  nearly 
equal,  the  head  and  trunk  forming  one  part,  and  the  lower  ex- 
tremities the  other.  Generally,  the  former  are  somewhat  the 
longest ;  but  in  cases  of  unusual  corporeal  stature,  the  excess 
depends  upon  an  undue  length  of  the  inferior  extremities.  On 
the  contrary,  in  persons  of  little  height,  the  latter  have  not  been 
developed  in  proportion  to  the  trunk  of  the  body. 

The  pelvis,  as  a  whole,  is  a  conoidal  cavity,  having  its  base 
upwards,  and  the  summit  below.  Its  internal  surface  forms  an 
irregular  floor,  on  which  the  viscera  of  the  abdomen  are  sus- 
tained in  the  erect  position;  and  its  external  surface,  by  pro- 
jecting considerably  at  various  places,  establishes  very  favour- 
able points  for  the  origin  of  muscles. 

The  internal  surface  of  the  pelvis  is  divided  by  the  projection 
of  the  anterior  margin  of  the  base  of  the  sacrum,  and  by  the  li- 
nea  ilio-pectinea,  into  two  cavities;  the  upper  one  is  the  great 
pelvis,  and  the  lower  one,  the  little  pelvis.  The  great  pelvis  is 
the  base  of  the  cone,  and  presents  at  its  anterior  part  a  large  de- 
ficiency, which  is  supplied  in  the  fresh  subject  by  the  abdominal 
muscles.  The  little  pelvis  is  a  complete  bony  canal,  much 
deeper  behind  and  at  the  sides,  than  in  front.  Its  depth,  behind, 
is  formed  by  the  whole  length  of  the  sacrum  and  coccyx ;  at  the 


THE    PELVIS.  103 

sides,  by  the  bodies  of  the  ischia  and  a  small  part  of  the  ilia ; 
and,  in  front,  only  by  the  length  of  the  bodies  of  the  pubes. 

The  upper  orifice  of  the  lesser  pelvis  is  called  its  superior 
strait:  it  is  somewhat  oval,  and  looks  obliquely  forwards  and 
upwards.  Its  axis  may  be  indicated  by  a  line  drawn  from  the 
extremity  of  the  coccyx  to  a  point  an  inch,  or  thereabouts,  be- 
low the  umbilicus.  The  inferior  orifice  of  the  lesser  pelvis  is 
called  the  inferior  strait.  Its  margins  in  the  naked  skeleton  are 
very  unequal,  for  it  presents  three  very  deep  notches,  two  late- 
rally, and  one  in  front.  The  first  are  formed  by  the  external 
margins  of  the  sacrum  and  coccyx,  contributing  to  deepen  the 
sciatic  notch,  which  already  is  formed  in  each  os  innominatum- 
The  third  one  is  formed  by  the  convergence  of  the  rami  of 
the  pubes  and  ischia  of  the  opposite  sides,  and  constitutes  the 
arch  of  the  pelvis  of  authors,  sometimes  called  the  arch  of  the 
pubes.  The  axis  of  the  lower  strait,  it  is  clear,  must  have 
a  very  different  direction  from  the  axis  of  the  superior,  and 
is  indicated  by  a  line  drawn  from  the  lower  part  of  the  first 
bone  of  the  sacrum,  through  the  centre  of  this  opening.  The 
cavity  of  the  lesser  pelvis  is  increased  considerably  behind,  by 
the  curvature  of  the  sacrum;  this,  however,  is  not  uniform,  as 
the  sacrum  is  much  more  curved,  as  well  as  longer  in  some  indi- 
viduals than  in  others.  The  planes  of  the  ischia  are  not  paral- 
lel with  one  another,  but  converge  slightly  from  above,  in  con- 
sequence of  which  the  transverse  diameter  of  the  lower  strait  is 
rather  smaller  than  the  transverse  diameter  of  the  superior  strait. 

Difference  of  the  Pelvis  in  the  Male  and  Female. 

There  are  several  well  marked  peculiarities  in  the  fully  de- 
veloped pelvis  of  either  sex. 

The  ossa  ilia  are  larger,  less  concave,  and  more  horizontal  in 
the  female.  The  superior  strait  is  also  larger,  and  more  round: 
its  transverse  diameter  always  exceeds  the  antero-posterior; 
whereas,  the  latter,  in  the  male,  frequently  is  found  the  longest. 
The  lesser  pelvis  is  also  more  capacious  in  women.  The  crura 
of  the  pubes  and  ischia,  are  not  so  long  as  in  men;  but  they  di- 
verge more,  and  join  at  the  under  part  of  the  symphysis  pubis 
by  a  large,  regularly  rounded  arch;  whereas,  in  men,  the  arch 
as  it  is  called,  is  merely  an  acute  angle. 


104  SKELETON. 

The  os  sacrum  in  women  is  shorter,  more  concave,  and  is 
also  broader  in  proportion  to  its  length.  The  spaces,  vertically, 
between  its  foramina  in  front  are  very  small,  forming  a  sort  of 
ridges,  which  give  to  the  bone  the  appearance  of  having  been 
compressed  in  its  length. 

The  distance  between  the  upper  and  lower  straits,  or  in  other 
words,  the  depth  of  the  small  pelvis  in  women,  is  not  so  great 
as  in  men:  this  arises  from  the  comparative  shortness  in  the 
length  of  the  pubes,  of  the  ischia,  and  of  the  sacrum,  as  just 
mentioned.  The  cartilaginous  joining  of  the  pubes  is  thicker 
in  women.  The  diameters  of  the  inferior  strait,  like  those  of 
the  superior,  are  longer  in  females. 

Accoucheurs  have  attached  much  importance  to  the  direction 
and  length  of  the  diameters  of  the  small  pelvis  in  well  formed 
women.  At  an  average  they  are  as  follow.  The  superior  strait 
presents  three  diameters:  The  first  or  antero-posterior  extends 
from  the  upper  extremity  of  the  symphysis  pubis,  to  the  mid- 
dle of  the  projection  of  the  sacrum  at  its  superior  margin,  and 
measures  four  inches :  The  second  diameter,  or  the  transverse, 
crosses  the  first  at  right  angles,  and  extends  from  the  middle  of 
one  side  of  the  strait  to  the  corresponding  point  on  the  other; 
it  measures  five  inches:  The  oblique  diameter  extends  from 
the  sacro-iliac  junction  of  one  side  to  the  linea  ilio-pectiniaover 
the  acetabulum  of  the  other,  and  measures  four  inches  and  a 
half,  sometimes  more.* 

At  the  inferior  strait,  the  antero-posterior  diameter  is  from 
the  lower  part  of  the  symphysis  pubis  to  the  lower  end  of  the 
sacrum,  and  measures  five  inches.!  As  the  coccyx,  in  child- 
bearing  women,  is  moveable,  its  projection  forwards  is  not 
taken  into  the  account,  because  it  recedes  by  the  pressure  of 
the  child's  head,  and  does  not  resist  its  passage:  in  some  cases, 
however,  it  is  unfortunately  fused  into  the  sacrum,  and  there- 
fore perfectly  rigid,  which  will  diminish  this  diameter  at  least 
an  inch.  The  transverse  diameter  of  the  inferior  strait  is 
drawn  from  the  middle  of  the  internal  margin  of  the  tuberosity 
of  one  ischium,  to  the  corresponding  point  on  the  other,  and 
measures  four  inches. 


*  See  Dewees'  System  of  Midwifery,  7th  edition,  1835,  p.  28, 
t  Dr.  Dewees  says  four.     Loc.  cit. 


THE  PELVIS.  105 

The  depth  of  the  little  pelvis,  in  the  female,  at  the  symphysis 
pubis,  is  an  inch  and  a  half;  at  the  posterior  part  four  inches, 
or  five  if  we  include  the  coccyx ;  and  at  the  side  three  inches 
and  a  half.  There  are  many  other  details  connected  with  the 
measurements  of  the  pelvis,  which  are  mentioned  by  systematic 
writers  on  midwifery. 


SECT.  VI. DEVELOPMENT  OF  THE  PELVIS. 

Three  points  of  ossification  are  observable  in  the  os  innomi- 
natum  of  the  early  foetus :  one  is  at  the  superior  part  of  the 
ilium,  another  is  at  the  tuberosity  of  the  ischium,  and  the  third 
is  at  the  angle  of  the  pubes.  The  radii  of  ossification  from 
these  centres,  have  extended  themselves  considerably  at  birth, 
so  as  to  sketch  out  the  forms  of  the  bones  to  which  they  re- 
spectively belong.  But  these  bones  are  separated  from  one 
another  by  cartilage,  and  do  not  coalesce  till  years  afterwards. 
The  union  or  fusion  of  the  ilium  and  pubes  then  occurs  at  the 
ilio-pectineal  eminence,  over  the  acetabulum,  and  partly  in  this 
cavity;  the  ilium  and  ischium  join  in  the  acetabulum  princi- 
pally, and  the  ischium  and  pubes  unite  by  their  respective 
erura  at  the  middle  of  the  internal  side  of  the  foramen  ovale. 
All  the  points  of  the  os  innominatum,  most  remote  from  the 
primitive  centres  of  ossification,  are  cartilaginous  at  birth:  as, 
for  example,  the  crest,  the  spinous  processes,  the  tuberosity, 
and  even  the  component  parts  of  the  acetabulum.  The  latter 
cavity  has  then  a  triangular  shape,  and  from  its  very  flexible 
and  yielding  condition,  is  incapable  of  affording  a  strong  point 
of  support  to  the  trunk  in  the  erect  position. 

At  birth,  the  middle  parts  of  the  os  sacrum,  which  are  em- 
ployed in  protecting  the  spinal  marrow,  are  more  advanced  in 
their  ossification  than  its  lateral  parts.  The  five  pieces  which 
compose  it,  are,  like  the  bodies  of  the  true  vertebrae,  of  a 
rounded  shape.  The  processes  behind  are  cartilaginous.  The 
coccyx  is  extremely  small,  and  scarcely  presents  any  ossifica- 
tion whatever. 

The  pelvis  of  the  foetus,  at  birth,  is  smaller  in  proportion  than 
the  superior  portions  of  the  trunk;  this  is  one  of  the  reasons 
why  the  abdomen  is  so  projecting.  The  lesser  pelvis  is  so 


106 


SKELETON. 


small  and  shallow,  that  the  bladder,  even  in  the  undistended 
state,  cannot  be  accommodated  by  it,  but  is  contained  princi- 
pally by  the  abdomen.  Its  transverse  diameter  is  much  short- 
er than  the  others.  The  superior  strait  faces  much  more 
forwards  than  in  the  adult. 


SECT.  VII. ON  THE  MECHANISM  OF  THE  PELVIS. 

The  pelvis  has  an  important  part  in  the  several  actions  of 
standing  and  of  locomotion;  besides  its  usefulness  in  giving  a 
support  to  the  viscera  of  the  abdomen,  and  in  having  attached 
to,  and  contained  within  it,  the  organs  of  generation. 

In  standing,  the  pelvis  is  impelled  by  two  opposing  forces,  in 
consequence  of  the  attachment  of  the  vertebral  column  at  its 
hind  part,  and  of  the  ossa  femorum  at  its  anterior  lateral  parts. 
The  weight  of  the  head  and  of  the  upper  parts  of  the  body, 
falling  upon  the  sacrum,  acts  upon  a  lever,  which  is  represent- 
ed by  the  distance  between  the  acetabula  and  the  sacro-iliac 
junction,  and  has  a  tendency  to  depress  the  posterior  part  of 
the  pelvis,  by  rotating  it  upon  the  heads  of  the  thigh  bones. 
This  movement  is  obviated  by  the  iliacus  internus,  psoas  mag- 
nus,  and  some  other  muscles,  which  keep  the  front  of  the  pelvis 
from  rising  up.  It  is  also  prevented  by  the  principal  weight 
of  the  trunk  being  in  front  of  the  spine,  and  therefore  inclining 
forwards,  so  that  the  centre  of  gravity,  in  the  erect  position, 
gives  a  continual  tendency  to  fall  forwards  instead  of  back- 
wards. 

The  wedge-like  shape  of  the  sacrum  is  highly  favourable  to 
the  erect  position:  from  having  it's  base  upwards,  whenever 
the  weight  of  the  trunk  is  thrown  upon  it,  it  is  driven  down 
between  the  ossa  innominata,  and  has  the  tightness  of  its  arti- 
cular connexion,  therefore,  muc«h  increased  by  the  position 
which  it  is  intended  to  sustain.  In  illustration  of  the. usefulness 
of  the  triangular  or  wedge-like  shape  of  the  sacrum,  it  may  be 
observed,  that  it  is  much  less  so  in  animals  which  are  intended 
to  go  upon  all  fours  than  in  the  human  subject. 

The  articulation  of  the  several  bones  of  the  pelvis  with  each 
other,  is  so  close  as  not  to  admit  of  any  motion  between  them, 
with  the  exception  of  the  os  coccygis,  and  of  the  relaxation 


THE  THORAX.  107 

peculiar  to  pregnancy.  The  pelvis,  however,  has  upon  the 
spine,  flexion,  extension,  lateral  inclination,  and  rotation ;  the 
latter  being  performed  by  a  series  of  very  slight  twists  of  the 
lumbar  vertebra  upon  each  other.  Like  all  other  motions,  it 
is  much  extended  by  habit  in  early  life.  Of  this  I  have  seen 
an  instance,  in  an  adult  Indian,  who,  from  infancy,  had  been 
deprived  entirely  of  the  use  of  the  lower  extremities;  but  who, 
by  being  seated  in  a  large  wooden  bowl,  with  a  round  bottom, 
and  having  his  legs  drawn  up  in  a  squatting  position,  could,  by 
alternate  twists  of  the  spine,  with  the  assistance  of  a  short  staff 
in  each  hand,  move  with  surprising  speed  over  a  plain  surface. 


SECT.  VIII. — OF  THE  THORAX. 

The  thorax  is  the  upper  part  of  the  trunk,  and  is  formed  by 
the  dorsal  vertebra?  behind,  by  the  sternum  in  front,  and  by  the 
ribs  with  their  cartilages  at  the  intermediate  spaces.  It  is  of 
a  conoidal  figure,  flattened  in  front,  somewhat  concave  behind, 
and  semi-cylindrical  on  the  sides.  The  interior  circumference 
corresponds  with  the  exterior,  with  the  exception  of  the  poste- 
rior part,  where,  owing  to  the  projection  of  the  column  of  dor- 
sal vertebra?,  a  partial  septum  exists  which  has  a  tendency  to 
divide  it  into  two  chambers.  The  superior  part  of  the  cone, 
or  its  summit,  is  much  smaller  than  the  inferior  part  or  the 
base,  and  presents  a  very  oblique  cordiform  foramen,  much 
lower  in  front  than  behind,  owing  to  the  superior  margin  of  the 
sternum  being  lower  than  the  first  dorsal  vertebra.  The  base 
of  the  thorax  is  a  very  large  opening:  its  lateral  and  posterior 
margins,  formed  by  the  ribs  and  their  cartilages,  present  a 
convexity  downwards;  but,  in  front,  where  the  latter  run  up  to 
join  the  sternum,  a  large  notch  is  formed  between  the  carti- 
lages of  the  opposite  sides,  into  the  apex  of  which  notch  the 
third  bone  of  the  sternum  projects. 


Of  the  Ribs. 

The  ribs,  costae,  (cotes,)  are  twenty-four  in  number,  twelve 
on  either  side.     Of  the  latter,  the  upper  seven,  in  consequence 


108  SKELETON. 

of  their  cartilages  joining  the  sternum,  are  called  the  sternal 
or  true  ribs,  and  the  lower  five,  from  their  cartilages  stopping 
short  of  the  sternum,  are  called  the  false  or  asternal  ribs. 
Cases  are  recorded  by  several  anatomists  of  there  being  eleven 
or  thirteen  ribs  on  a  side :  the  latter  I  have  seen  several  times, 
and  the  former  but  once  or  twice.  In  such  cases,  the  dorsal 
vertebrae  correspond  in  number  with  the  ribs.  In  the  instances 
of  redundance  which  have  come  under  my  notice,  the  last  rib 
looked  like  a  transverse  process  of  unusual  length,  belonging  to 
a  lumbar  vertebra.  The  superabundant  vertebra  constituted 
the  thirteenth  dorsal ;  but  was  formed  like  the  first  lumbar  as 
it  commonly  exists,  arid  the  last  lumbar  vertebra  was  entirely 
anomalous  in  its  shape,  being  intermediate  in  form  to  a  lumbar 
vertebra,  and  to  the  first  bone  of  the  sacrum. 

All  of  the  ribs  are  so  placed,  that  they  run  very  obliquely 
downwards  and  forwards  from  their  posterior  extremities. 
This  obliquity  becomes  the  more  striking  as  the  ribs  increase 
successively  in  length.  The  first  rib,  for  example,  articulating 
by  its  posterior  extremity  with  the  first  vertebra  of  the  back, 
has  its  anterior  extremity  nearly  on  a  horizontal  line  with  the 
lower  part  of  the  third  dorsal  vertebra.  The  seventh  rib  has 
its  anterior  extremity  on  a  horizontal  line  with  the  lower  mar- 
gin of  the  last  dorsal  vertebra,  notwithstanding  its  posterior 
extremity  articulates  with  the  seventh  vertebra.  The  same 
sort  of  comparison  might  be  usefully  instituted  in  regard  to  all 
the  ribs,  in  which  case  the  rule  will  be  found  closely  applicable, 
with  the  slight  exception  of  the  two  or  three  last  ribs.  The 
ribs  are  nearly  parallel  to  each  other  in  this  obliquity,  allowance 
being  made  for  the  effect  which  the  obliquity  of  the  sternum 
has  in  causing  a  greater  separation  of  their  anterior  extremities 
from  each  other,  than  exists  at  their  posterior  extremities. 

Common  points  of  resemblance  between  the  Ribs. — Each  rib 
is  paraboloid ;  presents  an  external  and  an  internal  surface ;  an 
upper  and  a  lower  margin;  a  sternal  and  a  vertebral  extre- 
mity. 

The  external  surface  of  each  rib  is  convex,  while  its  internal 
surface  is  concave.  The  former  presents,  not  far  from  the  ver- 
tebral extremity,  an  oblique  ridge,  occasioned  by  the  insertion 
of  the  sacro-lumbalis  muscle.  It  is  precisely  at  this  line  that  a 


THE  THORAX.  109 

curvature  somewhat  abrupt,  takes  place,  which  is  the  angle  of 
the  rib.  Between  the  angle  and  the  transverse  process  of  the 
vertebra,  each  rib  is  rather  more  narrow  and  cylindrical  than  it 
is  in  advance  of  the  angle.  The  superior  margin  of  the  rib  is 
rounded  and  somewhat  rough,  for  the  insertion  of  the  intercostal 
muscles,  while  the  inferior  margin  is  brought  to  a  thin,  cutting 
edge.  Just  within,  and  above  'the  latter,  is  a  fossa  beginning 
somewhat  nearer  to  the  spine  than  the  angle  of  the  rib,  and 
ceasing  about  one-third  of  the  whole  length  of  the  rib,  short  of 
its  anterior  extremity.  It  contains  the  intercostal  vessels  and 
nerve.  From  the  upper  margin  of  this  fossa  arises  the  internal 
intercostal  muscle,  and  from  the  lower  the  external. 

The  anterior  extremities  of  the  ribs  are  thin  and  flattened, 
in  the  upper  eight  there  is  some  increase  in  their  breadth  at 
this  point,  and  in  all  there  is  an  oblong  pit  for  receiving  the  end 
of  the  corresponding  cartilage.  The  vertebral  extremity  of  the 
rib  is  its  head,  and  presents  two  flat  articular  surfaces,  separated 
by  a  ridge.  This  head  is  received  into  the  inter-vertebral  mat- 
ter, and  upon  the  articular  faces  of  the  adjoining  margins  of  the 
vertebrae.  A  small  depression  exists  upon  the  posterior  face  of 
the  rib  bordering  on  its  head,  for  containing  a  little  fatty  mass. 
About  an  inch  beyond  the  head,  at  the  posterior  under  surface 
of  the  rib,  is  a  tubercle,  presenting  a  smooth  articular  face,  for 
connecting  itself  with  the  transverse  process  of  the  vertebra. 
Just  beyond  this,  but  bordering  on  it,  is  a  much  smaller  tuber- 
cle, not  unfrequently  indistinct,  for  the  insertion  of  the  exter- 
nal transverse  ligament,  and  below  it  is  a  small  pit  for  the  lodge- 
ment of  fatty  matter  near  the  joint.  The  space  between  the 
greater  tubercle  and  the  head  of  the  rib  is  its  neck,  which  is  in 
contact  with  the  antero-superior  face  of  the  transverse  process 
of  the  vertebra,  and  has  a  sharp  ridge  on  its  upper  margin,  for  the 
insertion  of  the  internal  transverse  ligament. 

The  most  of  the  ribs  have  a  very  sensible  twist  in  them,  by 
which  their  spinal  extremity  is  directed  upwards,  and  the  ster- 
nal extremity  downwards;  from  which  it  results,  that  the  whole 
length  of  the  rib  cannot  be  brought  into  contact  with  a  hori- 
zontal plane. 

Differences  in  Ribs. — Though  there  are  many  common  points 
VOL.  I.— 10 


110  SKELETON. 

of  resemblance  among  the  ribs,  yet  there  are,  also,  some  well 
marked  peculiarities.  The  ribs  increase  successively  in  length 
from  the  first  to  the  seventh  inclusively ;  they  then  decrease : 
the  last  is  not  only  the  smallest,  but  not  unfrequently  the  shortest. 
The  angles  of  the  ribs  increase  in  their  distance  from  the  spine, 
from  the  first  to  the  last  rib.  The  angle,  however,  of  the  first 
rib,  is  not  well  marked,  from  its  being  so  near  the  tubercle; 
neither  is  the  angle  of  the  last,  from  its  being  so  near  the  ante- 
rior extremity.  The  oblique  ridges  constituting  or  marking 
off  the  angles,  are  placed  one  above  the  other,  in  the  same  line. 
This  gives  to  the  back  of  the  thorax  a  triangular  flatness,  the 
base  of  which  is  below.  The  projection  backwards  of  the  angles 
of  the  ribs,  along  with  that  of  the  spinous  processes  of  the  ver- 
tebrae, forms  on  each  side  of  the  latter  the  gutter,  which  is  filled 
up  by  the  large  muscles  that  keep  the  trunk  erect.  This  gutter 
is,  of  course,  broader  below. 

The  first  rib  is  more  circular  than  the  others.  Its  head  is 
spherical,  instead  of  presenting  two  articular  surfaces.  This 
rib  is  flat  above  and  below ;  its  margins  are  internal  and  exter- 
nal. It  has  no  groove  for  the  intercostal  vessels  and  nerve. 
About  the  middle,  the  upper  surface  is  marked  by  a  superficial 
oblique  fossa,  made  by  the  subclavian  artery ;  in  front  of,  and 
behind  which  is  a  small  rising,  marking  the  insertion  of  the  sea- 
leni  muscles.  The  second  rib  is  considerably  longer  than  the 
first,  and  has  its  flat  surfaces  obliquely  upwards  and  down- 
wards, so  as  to  round  off  that  part  of  the  thorax.  The  four  in- 
ferior ribs  decrease  at  their  anterior  extremities,  or  become 
somewhat  tapering.  The  last  two  ribs  do  not  articulate  with 
the  transverse  processes,  and,  consequently,  have  no  corre- 
sponding tubercles.  As  their  heads  articulate  with  the  middle 
of  the  bodies  of  their  respective  vertebrae,  instead  of  with  the 
margins,  they  present  only  a  single  and  somewhat  convex  sur- 
face. The  eleventh  rib  is  marked  only  for  a  short  distance  in 
its  middle  by  the  fossa,  for  the  intercostal  vessels.  The  twelfth 
rib  has  no  mark  of  the  kind. 

There  is  an  augmentation  in  volume  from  the  second  to  the 
eighth  rib,  inclusively;  afterwards  they  decrease.  The  angles 
of  the  ribs  are,  successively,  more  and  more  obtuse. 

The  structure  of  the  rib  is  spongy,  covered  with  a  lamella  of 


THE  THORAX.  ill 

compact  bone.     The  spongy  structure  predominates  at  the  an- 
terior extremity,  for  there  the  rib  is  comparatively  soft. 


Of  the  Sternum. 

This  bone  constitutes  the  middle  front  part  of  the  thorax, 
and,  owing  to  the  obliquity  of  the  ribs,  has  its  superior  end  on 
a  horizontal  line  with  the  third  vertebra  of  the  back,  while  its 
inferior  extremity  is  on  a  horizontal  line  with  the  eleventh  dor- 
sal vertebra.  It  is  also  placed  in  a  slanting  direction,  so  that 
the  lower  part  recedes  from  the  spine  much  farther  than  the 
upper. 

The  sternum  is  oblong,  somewhat  curved,  like  a  bow,  so  as 
to  be  convex  in  front,  and  concave  behind.  It  is  divided,  in 
the  adult,  into  three  distinct  pieces;  an  upper,  middle,  and 
lower,  which  are  held  together  by  cartilage  and  by  ligament ; 
but  not  unfrequently  in  advanced  life  these  pieces  are  all  fused 
into  one,  by  bony  union.  The  first  and  middle  parts  join  where 
the  second  rib  is  articulated,  and  the  middle  and  lower  where 
the  seventh  rib  articulates.  At  these  points  there  is  a  well 
marked  transverse  ridge,  both  anteriorly  and  posteriorly,  and 
between  them  on  the  front  of  the  bone,  there  are  other  ridges 
not  so  strong,  indicating  the  original  separation  of  the  bone  into 
several  other  distinct  pieces.  The  lateral  margins  of  the  ster- 
num are  somewhat  elevated  where  the  ribs  articulate. 

The  upper  end  of  the  sternum  is  both  thicker  and  broader 
than  the  lower  end.  Where  tke  first  and  second  parts  join, 
there  is  a  narrowing  of  the  two :  the  same  occurs  where  the  se- 
cond and  third  pieces  unite. 

The  first  or  upper  bone  of  the  sternum,  has  an  irregular 
square  figure  ;  it  projects  somewhat  above,  and  is  slightly  hol- 
low below.  It  is  scooped  out  at  the  superior  margin,  and  pre- 
sents a  point  at  each  end  of  the  scoop.  At  the  side  of  the  lat- 
ter is  a  concave  and  rounded  surface,  for  articulating  with  the 
clavicle ;  just  below  which  is  a  rough  surface,  for  the  cartilage  of 
the  first  rib.  The  bone  diminishes  much  in  breadth  from  this 
point,  and  terminates  by  a  narrow  oblong  face,  joining  it  to  the 
second  piece.  At  each  side  of  this  junction  both  pieces  con- 
tribute to  a  fossa  for  the  cartilage  of  the  second  rib. 


112  SKELETON. 

The  second  bone  of  the  sternum  is  longer  and  narrower  than 
the  first.  At  its  lower  part  it  increases  somewhat  in  breadth, 
and  then  terminates  by  being  rounded  ofFon  either  side,  so  that 
its  margins  converge  towards  each  other.  The  sides  of  this 
piece  afford  complete  pits  for  the  third,  fourth,  fifth,  and  sixth 
ribs;  the  pit  for  the  seventh  is  common  to  it  and  the  third  bone, 
as  the  pit  for  the  second  rib  is  common  to  it  and  the  first  bone. 
The  sixth  and  seventh  pits  are  in  contact,  the  fifth  is  very  near 
the  sixth,  the  fourth  is  about  half  an  inch  above  the  fifth.  On 
viewing  the  whole  side  of  the -sternum,  it  will  be  observed  that 
the  distances  between  the  pits  decrease,  successively,  from  the 
first  to  the  last. 

The  third  bone  of  the  sternum,  in  the  young  adult,  is  fre- 
quently in  a  great  degree  or  wholly  cartilaginous,  hence,  the 
name  of  xyphoid  cartilage  (cartilago  xyphoides  or  ensiformis) 
has  been  applied  to  it.  It  is  thin,  varies  remarkably  in  its 
breadth  in  different  individuals,  and  has  the  lower  extremity 
sometimes  turned  forwards  and  sometimes  backwards,  but  most 
frequently  it  is  inclined  or>ly  slightly  forwards.  The  base  of 
this  piece  presents  a  narrow  oblong  surface  for  articulating  with 
the  second  bone,  at  each  end  of  which  is  the  half  fossa  for  the 
seventh  rib.  The  margins  of  the  ensiform  cartilage  are  thin, 
and  have  the  transverse  muscles  of  the  abdomen  inserted  into 
them.  Sometimes  the  lower  extremity,  instead  of  being  point- 
ed, is  bifurcated. 

The  sternum  is  composed  of  a  spongy  texture,  enveloped  by 
a  thin  layer  of  compact  substance.  Its  strength  depends,  in  a 
great  degree,  on  its  ligamentous  covering. 


SECT.  IX. OF  THE  CARTILAGES  OF  THE  RIBS. 

These  are  placed  at  the  anterior  extremities  of  all  the  ribs, 
the  seven  superior  of  which  they  unite  to  the  sternum  by  the 
sychondrosis  articulation.  The  length,  breadth,  and  direction 
of  these  cartilages  are  far  from  being  uniform. 

The  first  costal  cartilage  is  short;  the  following  ones  increase 
in  length,  successively,  to  the  seventh,  inclusively.  The  carti- 


CARTILAGES  OF  THE  RIBS.  113 

lages  of  the  false  or  abdominal  decrease,  successively,  in  length 
from  the  eighth  to  the  twelfth,  inclusively;  the  last  is  a  mere 
tip  to  the  end  of  the  rib.  The  breadth  of  the  first  cartilage  is 
considerable  near  the  sternum;  the  succeeding  ones  are  not  so 
large  at  this  point.  With  the  exception  of  the  first  three,  the 
costal  extremities  of  the  cartilages  are  larger  than  the  sternal; 
and  they  become  more  rounded  as  they  advance  to  the  latter. 
The  cartilages,  in  point  of  magnitude,  generally,  will  be  found 
in  proportion  to  the  size  of  the  ribs  with  which  they  articulate. 
The  sixth  and  seventh  are  joined  together,  and  are  spread  ouc 
at  their  middle,  which  gives  there  an  increase  of  breadth,  and 
permits  them  to  touch,  and  sometimes  to  coalesce. 

The  first  cartilage  goes  obliquely  downwards  in  the  direction 
of  the  rib  to  which  it  belongs,  in  order  to  join  the  sternum. 
The  second  and  the  third  cartilages  are  nearly  horizontal,  but 
inclining  a  little  upwards  in  their  progress;  the  fourth,  fifth, 
sixth,  and  seventh,  pass,  successively,  more  and  more  obliquely 
upwards  to  the  sternum,  in  consequence  of  the  increasing  length 
of  the  ribs  requiring  them  to  traverse  a  longer  space  to  reach 
this  bone.  From  the  direction  of  tlae  cartilages  being  oblique- 
ly upwards,  while  that  of  the  ribs  is  obliquely  downwards,  the 
angle  formed  near  the  rib  at  the  base  of  the  c.irtilage,  where  the 
latter  begins  first  to  turn  upwards,  is  less  obtuse  in  the  lower 
cartilages  than  in  the  upper.  The  obliquity  of  these  cartilages 
is  also  very  manifest,  by  comparing  them  with  the  side  of  the 
sternum:  with  it  they  form  a  very  acute  angle  below,  and  a  very 
obtuse  one  above. 

The  cartilages  of  the  false  ribs,  successively,  decrease  in 
length,  to  terminate  in  front  by  small  tapering  extremities. 
The  first  is  united  by  ligaments,  somewhat  closely,  to  the  last 
true  or  sternal,  and  is  occasionally  sent  forwards  fully  to  the 
sternum.  The  others  are  united  more  loosely,  in  such  a  way 
that  the  anterior  extremity  of  the  one  lies  agains^  the  inferior 
margin  of  that  which  is  above.  The  eleventh  and  twelfth  car- 
tilages are  generally  too  short  to  touch  the  ones  above,  they 
therefore  are  fixed  principally  by  a  connexion  with  the  abdomi- 
nal muscles.  Their  ribs  are  much  more  moveable  than  any 
others,  and  have  been  called  floating,  from  that  cause. 

There  is  some  difference  between  the  two  extremities  of  the 
cartilages;  the  posterior  or  costal  is  a  small,  convex,  unequal 

10* 


114  SKELETON. 

surface,  very  closely  united  to  the  anterior  extremity  of  the  cor- 
responding rib.  The  other  or  sternal  extremity  in  the  sternal 
cartilages,  offers  a  smooth  articular  face,  which  is  angular  or 
convex,  according  to  the  shape  of  the  cavity  in  the  sternum  with 
which  it  has  to  articulate.  The  three  first  ahsternal,  and  the 
last  sternal  cartilage,  make,  to  the  lower  part  of  the  thorax,  a 
broad  and  well  marked  margin,  convex  in  front  and  concave 
behind. 

The  cartilages  of  the  ribs  are,  in  persons  of  middle  age,  white, 
flexible,  and  very  elastic.  They  are  dissolved  very  slowly  in 
boiling  water;  by  which  they,  if  young,  are  reduced  to  gelatine, 
otherwise  their  solubility  is  very  imperfect.  They  have  a 
structure  differing,  in  some  respects,  from  other  cartilages;  when 
dried,  and  exposed  to  the  action  of  the  atmosphere,  they  are^, 
seen  to  consist  of  an  immense  number  of  small  thin  plates,  placed 
end  to  end,  and  separated  by  deep  fissures.  M.  Herissant  de- 
scribes these  plates  as  interlaced  one  with  another,  and  forming 
a  kind  of  spiral,  the  regularity  of  which  is  interrupted  by  small 
cartilaginous  projections,  uniting  the  plates  to  each  other.* 
These  cartilages  have  a  gres»t  disposition  to  ossify,  which  is  ma- 
nifested in  most  individuals  somewhat  advanced  in  life.  The 
ossification  begins  in  their  centre,  and  advances  to  the  circum- 
ference, and  is  always  preceded  by  a  yellowish  tinge.  When 
they  are  fully  ossified,  like  the  ribs,  they  are  cellular  within, 
and  compact  externally,  and  are  continuous  with  the  ribs,  there 
being  no  interval:  in  such  cases,  the  distinction  from  the  ster- 
num is  generally  kept  up  by  the  preservation  of  the  joint,  with 
the  exception  of  the  first,  which  is  fused  into  it.  The  complete 
ossification  of  the  first  cartilage  is  not  uncommon;  the  others, 
though  there  is  generally  in  old  persons  a  considerable  deposite 
of  bone  in  them,  are  seldom  fully  ossified.  In  neither  case, 
however,  is  it  common  to  see  such  a  perfect  continuity  of  bone 
between  the  rib  and  sternum,  that  the  junction  may  not  be  dis- 
solved at  one  point  or  another  of  this  space  by  the  action  of 
boiling  water:  at  least,  after  very  numerous  observations  on  this 
subject,  I. do  not  remember  to  have  met  with  a  single  instance 
of  it. 

*  Acad.  des  Sciences,  an.  1748. 


DEVELOPMENT  OF  THE  THORAX.  115 


SECT.  X. — OF  THE  DEVELOPMENT  OP  THE  THORAX. 

In  the  foetus  the  shape  of  the  thorax  differs  much  from  that 
of  the  adult,  in  the  greater  comparative  extent  of  its  antero-pos- 
terior  diameter,  and  in  the  projection  of  the  sternum.  The  state 
of  the  thoracic  viscera,  at  this  period,  calls  for  such  an  arrange- 
ment; as  the  heart  and  thymus  gland,  which  are  in  the  middle, 
have  a  considerable  extent,  whereas,  the  lungs  are  still  collapsed 
from  the  emptiness  of  their  air  cells.  The  ribs  are  but  little 
curved  at  their  posterior  parts,  the  angle  being  by  no  means 
well  formed,  in  consequence  of  which,  the  fossa  on  each  side  of 
the  bodies  of  the  vertebrae,  in  the  thorax,  is  not  so  deep;  neither 
is  the  fossa  behind,  on  each  side  of  the  spinous  processes,  so 
fully  marked.  The  superior  opening  of  the  thorax  is  more 
round  from  the  increase  of  the  antero-posterior  diameter.  The 
inferior  opening  is  extremely  large,  both  from  the  elevation  of 
the  sternum,  and  from  the  pressure  of  the  abdominal  viscera,  of 
which  the  liver,  from  its  great  extent,  is  a  principal  agent.  The 
vertical  diameter  of  the  thorax  is  %small,  from  the  ribs,  particu- 
larly the  lower  ones,  being  pressed  up  one  against  the  other,  by 
the  diaphragm,  acted  on  by  the  abdominal  viscera. 

The  bones  individually  are  in  the  following  state  at  birth. 
The  ribs  are  almost  completed,  the  heads,  where  they  join  the 
spine,  being  in  a  state  nearly  as  perfect  as  at  any  subsequent  pe- 
riod of  life,  and  not  by  any  means  in  the  condition  of  a  cartila- 
ginous epiphysis,  as  is  presented  in  the  extremities  of  the  cy- 
lindrical bones  generally.  These  bones,  as  Bichat  very  justly 
observes,  are  destined  to  a  function  which  commences  imme- 
diately upon  birth,  and  which  requires  in  them  as  much  perfec- 
tion then,  as  they  have  in  the  adult.  For  respiration  is  different 
from  locomotion,  the  latter  requires  a  species  of  education,  which 
may  be  given  gradually,  whereas  one  respires  from  the  begin- 
ning as  he  will  respire  always.  The  sternum,  which  is  less  im- 
mediately connected  with  breathing,  and  only  contributes  to 
the  general  solidity  of  the  thorax  by  completing  its  circumfe- 
rence, is  in  a  state  almost  cartilaginous,  and  presents  only  nuclei 
of  ossification  in  its  several  pieces. 

At  the  instant  of  birth,  a  great  change  is  produced  in  the  di- 


116  SKELETON. 

mensions  of  the  thorax.  The  lungs,  from  being  in  a  collapsed 
and  solid  state,  suddenly  suffer  an  expansion  of  their  cells  by 
the  introduction  of  air  into  them,  and  increase  twice  or  three 
times  in  magnitude.  This  is  accomplished  by  the  elevation 
of  the  ribs,  and  the  consequent  increase  in  the  transverse  dia- 
meter of  the  thorax:  it  becomes  a  condition  that  for  ever  after- 
wards remains,  so  that  the  lungs,  even  upon  death,  continue  to 
have  their  air  cells  distended,  and  do  not  return  to  a  perfectly 
collapsed  state.  The  action  of  the  diaphragm  is  but  small  in 
the  earliest  periods  of  life,  owing  to  the  size  and  pressure  of  the 
abdominal  viscera  against  it;  respiration  is  then  principally  car- 
ried on  by  the  elevation  and  depression  of  the  ribs,  and  by  their 
being  rolled  outwards,  a  motion  which  the  flexibility  of  their 
cartilages  and  the  looseness  of  their  articulating  surfaces  favour 
very  much. 

At  the  age  of  puberty  the  thorax  experiences  a  remarkable 
augmentation.  Its  transverse  diameter  is  sensibly  increased, 
and  there  is  a  general  expansion  of  its  volume,  indicative  of  a 
healthy  and  vigorous  constitution.  Should  this  not  take  place, 
and  the  sternum  be  projected,  it  is  supposed  to  mark  a  disposi- 
tion to  consumption.  The  enlargement  of  the  thorax  is  un- 
doubtedly also  connected  with  a  development  of  the  organs  of 
generation  at  the  same  time.  The  exercise  of  the  latter  re- 
quires greater  vital  powers  than  exist  in  early  life,  and  the  pro- 
vision for  it  is  manifested  by  the  general  increase  of  vigour  and 
firmness  in  the  human  frame;  but  it  is  not  possible  to  point  out 
in  what  manner  the  sympathy  exists,  which,  on  the  develop- 
ment of  the  organs  of  generation,  extends  their  influence  to  the 
bony  structure  of  the  thorax. 


SECT.  XI. OF  THE  MECHANISM  OF  THE  THORAX. 

The  thorax  performs  two  very  important  offices  in  the  ani- 
mal machine:  the  first  is  to  contain  and  protect  the  organs  of 
circulation  and  respiration,  the  second  to  assist  in  the  function 
of  respiration,  and  perhaps  that  of  circulation.* 

The  mechanism  of  the  thorax  is  such  that  the  solidity  of  its 

*  A  very  interesting  paper,  on  this  subject,  lias  lately  been  presented  to  the 
French  Institute  by  M .  Barry. 


MECHANISM  OF  THE  THORAX.  117 

materials,  and  its  rounded  shape,  present  a  very  efficacious  de- 
fence to  its  viscera  from  the  influence  of  blows  on  its  outside. 
The  effects  of  the  latter  are  also  materially  diminished  by  the 
thickness  and  contraction  of  the  several  large  muscles  which  are 
placed  on  its  surface.  On  its  back  part  the  thick  longitudinal 
muscles  of  the  spine,  as  well  as  those  running  to  the  superior 
extremities,  fill  up  the  gutters  on  each  side  of  the  spinous  pro- 
cesses, and  make  a  fleshy  protuberance,  divided  into  two  by  the 
raphe  which  extends  the  length  of  the  back  over  the  spinous 
processes.  In  front  it  is  less  protected,  owing  to  the  sternum 
being  immediately  under  the  skin.  Nevertheless,  when  blows 
are  inflicted  on  this  part,  their  effects  are  much  diminished  by 
the  elasticity  of  the  cartilages  of  the  ribs,  and  by  the  direction, 
obliquely  downwards,  of  the  ribs  themselves;  both  of  which 
dispose  the  sternum  to  retreat  backwards,  and  to  yield  to  the 
impelling  force.  The  recession  will  take  place  more  readily  at 
the  moment  of  expiration;  and  when  the  muscles  which  elevate 
the  ribs  are  not  on  their  guard.  In  those  deliberate  exertions 
of  the  strength  of  the  thorax,  exhibited  by  individuals  lying 
down  on  their  backs,  and  sustaining  a  heavy  weight  on  the  ster- 
num, the  ribs  are  saved  from  injury  by  different  means.  The 
arched  form,  itself,  of  the  front  of  the  thorax,  is  of  considerable 
service  in  the  resistance  under  such  circumstances ;  this,  how- 
ever, would  be  easily  overcome,  and  the  ribs  would  break,  if 
the  arch  were  not  sustained  in  its  elevation  by  the  contraction 
of  the  large  muscles  on  its  sides ;  as  the  serratus  major,  the  pec- 
toralis  major  and  minor,  each  of  which,  by  acting  on  the  de- 
pressed anterior  extremities  of  the  ribs  and  their  cartilages,  has 
a  tendency  to  keep  them  elevated.  Fractures  of  the  ribs,  from 
blows  or  force  applied  in  front,  are  not  so  liable  to  occur  in  the 
part  stricken  as  in  the  point  feeling  the  greatest  momentum, 
which  from  the  semicircular  form  of  the  ribs  is  in  or  near  their 
middle :  this  exhibits  a  true  example  of  what  the  French  writers 
call  the  contre-coup.  Bichat  says,  that  the  fracture  by  contre- 
coup  is  much  more  common  when  the  individual  being  struck 
unexpectedly,  has  not  had  time  to  throw  his  muscles  into  a  state 
of  contraction,  for  the  protection  of  the  ribs. 

The  lateral  convexity  of  the  thorax  being  greater  than  that 
in  front  or  behind,  and  having  the  same  assistance  from  the 
muscles  mentioned,  presents  a  stronger  resistance  when  blows 


118  SKELETON. 

are  inflicted  directly  on  it.  Each  rib  represents  an  arch,  the 
summit  of  which  is  its  centre,  and  the  base  its  two  extremities. 
The  abutments  of  the  base  are,  the  sternum  at  one  end  and  the 
spine  at  the  other :  a  displacement  from  them  is  completely  pre- 
vented by  the  strength  of  the  ligamentous  attachments,  as  well 
as  by  the  form  of  the  surfaces.  Under  these  circumstances,  as 
fracture  occurs  preferably  to  dislocation,  it  is  generally  at  the 
point  stricken. 

The  abdominal  or  false  ribs,  from  their  want  of  attachment 
to  the  sternum,  present  a  very  different  condition.  Their  an- 
terior extremities,  therefore,  yield  readily,  and  are  driven  in- 
wards towards  the  abdomen. 

The  second  function  of  the  thorax,  relating  to  its  influence  on 
respiration,  is  executed  by  its  dilating  and  contracting,  whereby 
the  air  is  received  into,  and  expelled  from  it.  The  spine  is  the 
fixed  point  for  the  motions  of  the  ribs  in  respiration.  In  the  act 
of  dilatation,  the  capacity  of  the  thorax  is  augmented  in  three 
directions,  vertically,  transversely,  and  antero-posteriorly,  or 
from  the  sternum  to  the  spine.  The  vertical  augmentation  is  ac- 
complished by  the  diaphragm ;  and,  as  mentioned,  is  much  great- 
er proportionally  in  the  adult  than  in  the  infant,  from  the  greater 
comparative  size  of  the  abdominal  viscera  in  the  latter.  The 
transverse  augmentation  is  produced  by  the  successive  contrac- 
tion of  the  intercostal  muscles,  which  raise  the  ribs  upwards. 
The  first  rib  is  moved  inconsiderably,  in  consequence  of  its  short- 
ness and  of  its  continuity  with  the  sternum.  The  attachment  of 
the  scaleni  muscles  to  its  upper  surface,  serves  rather  to  give  a 
fixation  to  it,  and  to  prevent  it  from  being  drawn  down  by  the 
other  ribs,  than  to  produce  by  their  contraction  an  elevation  of 
it.  The  first  rib  may,  therefore,  be  considered  as  a  fixed  point. 
The  first  intercostal  muscles  contracting  from  it,  draw  up  the  se- 
cond rib,  which,  in  its  turn,  becoming  a  fixed  point  for  the  second 
intercostal  muscles,  they  contract  and  draw  up  the  third  rib,  and 
so  on  successively  to  the  last.  It  is  the  obliquity  of  the  ribs  from 
behind,  downwards  and  forwards,  which  enables  this  elevation  of 
them  to  produce  an  increase  in  the  lateral  diameter  of  the  thorax: 
without  such  obliquity,  their  elevation  would  not  have  the  ef- 
fect. But  the  obliquity  alone  could  be  of  but  little  service,  if 


MECHANISM  OF  THE  THORAX.  119 

the  anterior  extremities  of  the  ribs  were  not  attached  to  the 
sternum  by  cartilages,  which  have  to  ascend  in  order  to  reach 
it;  for  it  is  obvious  that  the  angle  of  the  cartilage  and  rib,  during 
their  elevation  by  the  intercostal  muscles,  has  a  tendency  to  en- 
large itself;  and  will,  in  doing  so,  increase  the  horizontal  dis- 
tance between  the  anterior  end  of  the  rib  and  the  sternum,  and 
consequently  increase  the  transverse  diameter  of  the  thorax. 
The  upper  ribs,  from  the  shortness  as  well  as  direction  of  their 
cartilages,  can  do  little  or  nothing  in  increasing  this  diameter. 

According  to  some  anatomists,  the  capacity  of  the  thorax  is 
also  augmented  by  a  rocking  motion  of  the  rib,  in  which,  the 
two  extremities  being  stationary,  the  middle  is  drawn  upward 
and  outward.  It  is  not,  however,  very  clear,  that  this  motion 
exists  to  much  extent,  in  the  adult,  as  the  posterior  articulations 
of  the  thorax  are  opposed  to  it. 

While  the  transverse  enlargement  of  the  thorax  is  going  on, 
a  simultaneous  motion  occurs  in  the  sternum,  and  in  consequence 
of  the  oblique  direction  in  which  the  ribs  run  to  it,  the  sternum 
is  caused,  by  the  elevation  of  their  bodies,  to  recede  from  the 
spine.  But,  as  the  ribs  increase  successively  in  length  from  the 
first  to  the  seventh,  each  lower  one,  in  its  elevation  from  the 
oblique  towards  the  horizontal  line,  has  its  anterior  extremity 
carried  proporlionably  farther  off  from  the  spine ;  hence,  the 
sternum  has  a  combined  movement  resulting  from  its  several 
attachments  to  the  ribs:  one  motion  elevates  it  as  a  whole,  ano- 
ther causes  it  to  recede  from  the  spine  as  a  whole:  and  the 
third  causes  its  lower  end,  from  the  increased  length  of  the  ribs 
there,  to  be  pushed  farther  from  the  spine  than  the  upper;  giving 
it,  thereby,  during  respiration,  a  slight  motion  backwards  and 
forwards,  resembling  that  of  a  pendulum.  This  latter  motion, 
however,  though  its  existence  is  clear,  is  riot  very  considerable, 
from  the  sternum  being  kept  in  check  by  the  tendinous  centre 
of  the  diaphragm,  as  one  may  prove  by  examining  his  own 
body.  The  enlargement  of  the  thorax,  in  its  antero-posterior 
diameter,  is  much  more  considerable  at  the  anterior  extremi- 
ties of  the  ribs,  because  there  they  are  comparatively  free.  In 
this  case,  the  cartilages  of  the  ribs  are  bent  forwards,  besides 
being  elevated. 

In  expiration,  the  movements  of  the  thorax  are  exactly  the 
reverse  of  what  they  are  in  inspiration,  and  alUts  diameters  are, 


120  SKELETON. 

consequently,  diminished.  Whatever  may  be  said  of  muscular 
influence  in  producing  this  change,  it  is  much  exaggerated.  It 
is  true,  that  there  are  certain  muscles  which  may  be  applied  to 
this  end,  as  the  abdominal,  and  also  some  on  the  back,  as  the 
longissimi  dorsi  and  sacro  lumbales;  but  that  they  are  actually 
so  engaged,  under  ordinary  circumstances,  is  rather  questiona- 
ble. In  observing  the  phenomena  of  natural  respiration,  when, 
by  position,  all  these  muscles  are  put  into  a  state  of  relaxation, 
it  does  not  appear  that  the  process  is  at  all  impaired  by  their 
being  thrown  out  of  action.  The  only  muscles,  therefore,  that 
seem  to  be  especially  appropriated  to  produce  expiration,  are 
few  and  small:  they  are  the  serrati  inferiores  postici,  one  on 
either  side  of  the  spine.  But,  when  the  lower  ribs  are  fixed  by 
the  several  muscles  inserted  into  them,  they  become  points  of 
support  to  the  upper  ones ;  and  then  the  intercostal  muscles  may 
officiate  in  expiration,  by  drawing  the  ribs  successively  down- 
wards, as  they  do,  in  inspiration,  by  drawing  the  ribs  succes- 
sively upwards. 

The  elasticity  of  the  cartilages,  by  which  these  bodies  are  en- 
abled to  return  from  the  constrained  state  in  which  they  were 
placed  by  inspiration,  has  also  been  supposed  important  to  ex- 
piration, by  Haller,  and  others.  The  power  thus  derived  is 
certainly  of  some  value;  but  has  much  less  than  has  been  at- 
tached to  it.  It  unquestionably  exists  in  early  and  middle  life," 
but  is  lost  in  old  age,  when  the  cartilages  ossify,  and,  therefore, 
are  deprived  of  elasticity.  The  true  and  efficient  cause  of  expi- 
ration appears  to  be  atmospheric  pressure,  upon  the  external 
parietes  of  the  thorax,  acting  along  with  the  natural  elasticity 
of  the  lungs.  The  lungs,  it  is  well  known,  when  in  a  state  of 
repose,  and  removed  from  the  thorax,  are  much  smaller  than 
the  cavities  which  they  fill  during  life.  They  have,  therefore,  a 
continual  disposition,  in  the  living  state,  to  return  to  the  size 
which  is  most  easy  to  them;  and,  when  they  are  dilated  by 
inspiration,  they  subsequently  contra<*t.  These  positions  are 
proved  conclusively,  by  the  condition  of  the  inferior  surface  of 
the  diaphragm,  in  a  healthy  and  entire  thorax:  where  this  mus- 
cle, in  consequence  of  atmospheric  pressure  from  without,  is 
driven  high  up  into  its  cavity.  Its  contraction  in  inspiration 
draws  it  down,  and  the  instant  that  the  contraction  ceases,  it  is 
impelled  upwards  again.  Now,  the  same  power  is  applied  to 


,    THE  CRANIUM.  121 

the  whole  periphery  of  the  thorax:  and  its  cavity  being  enlarged 
by  the  contraction  of  the  several  muscles  appropriated  to  the 
elevation  of  the  ribs;  the  moment  this  contraction  ceases,  the 
latter  are  impelled  downwards.  From  all  this  it  will  be  under- 
stood that  the  muscles,  by  creating  a  vacuum  in  the  lungs,  cause 
the  vacuum  to  be  filled  by  the  introduction  of  air  through  the 
trachea;  and  upon  their  ceasing  to  contract,  the  several  agents 
mentioned  cause  the  expulsion  of  the  same  air.  It  is  generally 
believed,  that  the  surface  of  the  lung  is  every  where  in  contact 
with  the  thorax;  it  appears,  however,  doubtful,  whether  there 
is  not  a  space  between  the  pleura  pulmonalis  and  diaphragmalis, 
particularly  at  the  most  posterior  and  inferior  part  of  the  dia- 
phragm. Certain  it  is,  that  adhesions  there,  are  much  less  com- 
mon than  in  other  parts  of  the  thorax. 

The  ligaments  at  the  spinal  extremities  of  the  ribs,  by  being 
put  on  the  stretch  in  inspiration,  have  also  some  tendency  to 
throw  down  the  ribs  in  expiration.  In  short,  the  contraction 
of  the  thorax  may  be  set  down  as  the  result  of  the  joint  action 
of  the  atmosphere,  the  cartilages  of  the  ribs,  the  ligaments,  the 
contraction  of  the  lungs,  and  the  muscles.  When  the  structure 
of  the  lung  is  so  altered  that  its  elasticity  is  impaired  or  de- 
stroyed, expiration  becomes  then  much  more  difficult. 


CHAPTER  II. 

OF  THE  HEAD. 

THE  head  is  placed  upon  the  upper  extremity  of  the  verte- 
bral column,  and  consists  in  a  considerable  number  of  bones, 
which  are  either  in  pairs,  or,  if  single,  have  the  two  sides  sym- 
metrical. Some  of  these  bones  form  a  large  cavity,  the  cranium, 
for  containing  the  brain;  the  others  are  employed  in  the  forma- 
tion of  the  nose;  of  the  orbit  for  the  eye-ball;  and  of  the  mouth. 
The  head,  for  the  most  part  ovoidal,  presents  very  striking  va- 
rieties of  form  between  different  individuals  and  different  na- 
tions. It  is  thought  by  physiologists,  that  the  moral  or  intel- 
lectual condition  of  a  people,  their  habits,  climate,  and  food, 

VOL.  I.— 11 


122  SKELETON, 


have  a  powerful  influence  in  producing  these  diversities.     The 
head  is  divided  into  cranium  and  face. 


SECT.  I. OF  THE  CRANIUM. 

The  Cranium  is  composed  of  eight  bones.  The  Os  Frontis, 
the  Os  Occipitis,  two  Ossa  Parietalia,  two  Ossa  Temporum,  the 
Os  S.phenoides,  and  the  Os  Ethmoides,  The  Os  Frontis  is  at 
the  front  of  the  cranium;  the  Os  Occipitis  is  at  its  hind  part;  the 
Ossa  Parietalia,  one  on  each  side,  form  its  superior  lateral  parts; 
the  Ossa  Temporum,  also  one  on  each  side,  form  its  inferior  la- 
teral parietes;  the  Os  Sphenoides  is  in  the  middle  of  its  bottom 
part;  and  the  Os  Ethmoides  is  at  the  fore  part  of  the  centre  or 
body  of  the  last  bone. 

The  cavity  thus  formed  for  the  brain,  has  three  diameters, 
which  may  be  learned  by  sawing  vertically  through  the  middle 
line  of  one  skull,  and  horizontally  through  the  cavity  of  another. 
The  first  diameter  is  the  longest,  and  extends  from  the  lower 
part  of  the  frontal  bone  to  the  protuberance  on  the  middle  of  the 
Interior  surface  of  the  os  occipitis;  it  is  commonly  about  six 
inches  and  a  half  long.  The  second  diameter  includes  the  space 
between  the  superior  margins  of  the  temporal  bones,  where  they 
are  most  distant  from  each  other,  and  passing  over  the  middle  of 
the  great  occipital  foramen,  is  about  five  inches.  The  third  di- 
ameter is  taken  from  the  centre  of  the  large  hole  in  the  occipital 
bone,  to  the  centre  of  the  suture  between  the  parietal  bones;  it  is 
about  five  inches,  also.  Rather  more  than  one-third  of  the  ca- 
vity of  the  cranium  is  placed  behind  the  second  diameter,  and  it 
diminishes  somewhat  abruptly;  but  in  front  of  this  diameter  the 
cavity  is  finished  more  gradually. 

When  the  face  is  separated  from  the  cranium,  the  exterior 
surface  of  the  latter,  excepting  its  base,  represents  tolerably  ac- 
curately the  form  and  proportions  of  its  cavity:  allowance  being 
made  for  the  large  sinuses  in  the  lower  part  of  the  frontal  bone, 
and  for  the  thinness  of  the  upper  parts  of  the  temporal  bones. 
The  diameters  mentioned,  can  only  represent  what  most  fre- 
quently happens,  for  daily  observation  proves  remarkable  de- 
partures from  them.  Sometimes  the  transverse  diameter  is  in- 
creased at  the  expense  of  the  longest,  which  gives  to  the  head  a 
flatness  before  and  behind.  On  other  occasions,  the  vertical  di- 


THE  CRANIUM.  123 

ameter  is  increased,  whereby  the  head  receives  a  conical  form. 
In  many  individuals  the  first  diameter  is  increased,  which  makes 
the  two  sides  of  the  cranium  more  parallel  and  flat  than  usual. 
The  elongation  of  the  transverse  diameter  is  the  most  common, 
and  that  of  the  vertical  the  least  so.  The  capaciousness  of  the 
cranium  is  much  the  same  in  adult  individuals  of  the  same  sex; 
from  which  it  may  be  inferred  that  the  excess  of  one  diameter 
is  obtained  generally  at  the  expense  of  the  other.  The  male 
cranium  is  more  capacious  and  thick  than  the  female. 

The  female  sex  is  less  liable  to  variations  in  these  proportionate 
diameters  than  the  male.  Stature  has  but  little  influence  on  the 
capaciousness  of  the  cranium,  as  giants  and  dwarfs  have  it  of  the 
same  size;  hence,  the  former  seem  to  have  very  small  heads, 
while  the  latter  appear  to  have  very  large  ones,  the  eye  being 
deceived  by  the  relative  magnitude  of  their  bodies. 

The  fact  seems  to  be  now  well  ascertained,  that  continued 
pressure,  or  rather,  resistance  in  a  fixed  direction,  made  upon 
the  cranium  of  a  growing  infant  will  change  its  natural  form. 
Peculiar  ideas  of  beauty  have  induced  certain  tribes  of  savages 
to  adopt  this  barbarous  and  unnatural  practice.  The  late  Pro- 
fessor Wistar*  showed  to  his  class,  in  1796,  a  Choctaw  Indian 
having  this  peculiarity;  and  a  tribe  now  existing  near  the  sources 
of  the  Missouri,  continues  the  practice  of  flattening  both  the  oc- 
ciput and  the  os  frontis. 

In  the  Wistar  Museum  we  have  ten  headst  of  Peruvian  In- 
dians, brought  from  the  Pacific  Ocean,  nine  of  which  bear  the 
strongest  evidence  of  having  been  flattened  by  pressure,  on  the 
os  frontis  and  on  the  os  occipitis.  The  possibility  of  effecting 
such  a  change  in  the  form  of  the  cranium  has  been  strongly  con- 
tested; and  Biehat,  who  admits  it,  acknowledges  that  he  was 
unable  to  produce  like  modifications  in  puppies,  kittens,  and 
India  pigs.  The  singular  change,  however,  which  is  wrought 
upon  the  feet  of  Chinese  ladies,  strongly  corroborates  the  opi- 
nion of  the  head  being  also  susceptible  of  artificial  modifications 
in  its  form.J 

*  System  of  Anat.  3d  edit.  vol.  i,  p.  73,  1824, 

t  Presented  by  Dr.  James  Corneck,  U.  S.  Navy,  to  the  late  Dr.  Physick. 

t  In  an  examination  of  an  adult  female  of  this  nation,  Among  Foy,  the  mea- 
surements were  two  inches  and  one-eighth  from  the  heel  to  the  end  of  the  small 
toe  ;  four  inches  and  three-quarters  from  the  heel  to  the  end  of  the  great  toe;  and 
the  circumference  of  the  ankle  six  inches  and  six-tenths. 


124  SKELETON. 

SECT.  II. OP  THE  INDIVIDUAL  BONES  OP  THE  CRANIUM. 

1.  Frontal  Bone,  (Os  Frontis,  Frontal) 

The  frontal  bone  forms  the  whole  anterior,  and  a  portion  of 
the  superior,  lateral  and  inferior  parietes  of  the  cranium.  It  is 
symmetrical,  and,  occasionally,  is  completely  divided  into  two 
bones  by  the  continuation  of  the  suture  between  the  parietal 
bones. 

Its  external  face  is  convex,  and  the  internal  concave.  On  the 
former  may  be  observed  a  line,  or  slightly  raised  ridge,  running, 
on  the  middle  of  the  bone  from  above  downwards,  which  is  ex- 
pressive of  the  original  separation  between  its  two  halves.  The 
front  surface  of  the  bone  is  terminated  on  either  side,  below,  by 
the  orbitary  or  superciliary  ridge,  a  sharp  and  arched  elevation, 
forming  the  upper  anterior  boundary  to  the  orbit  of  the  eye. 
This  ridge  terminates  outwardly  by  the  external  angular  pro- 
cess, and  inwardly,  by  the  internal  angular  process.  Just  above 
the  internal  half  of  the  orbitary  ridge  the  bone  is  raised,  by  the 
separation  of  its  tables,  into  the  superciliary  or  nasal  protube- 
rance or  boss.  Between  the  internal  angular  processes  a  broad 
serrated  surface  exists,  by  which  the  frontal  bone  is  united  to  the 
nasal  bones,  and  to  the  nasal  processes  of  the  superior  maxil- 
lary bones.  The  centre  of  this  surface  is  elevated  into  the 
nasal  spine,  which  serves  as  an  abutment  to  the  nasal  bones, 
and  resists  any  force  which  might  tend  to  drive  {hem  inwards. 
On  its  exterior  lateral  surface,  behind  the  external  angular 
process,  the  frontal  bone  presents  a  concavity,  bounded  above 
by  a  well  marked  semi-circular  ridge,  and  intended  for  the 
lodgement  of  a  part  of  the  temporal  muscle. 

On  each  side  of  the  front  of  the  bone  near  its  middle  a  promi- 
nence exists,  most  frequently  better  marked  in  infancy  than  in 
advanced  life,  and  called  by  the  French  the  frontal  protube- 
rance. 

Proceeding  backwards  from  the  inferior  part  of  the  bone  are 
the  two  orbitar  processes,  concave  below  and  convex  above. 
They  are  much  thinner  than  other  parts  of  the  bone,  and  are 
separated  by  an  oblong  opening  which  receives  the  ethmoidal 
bone.  A  depression,  large  enough  to  receive  the  end  of  a  fin- 
ger, is  at  the  exterior  anterior  part  of  the  orbitar  process,  be- 


THE  CRANIUM.  125 

ing  protected  by  the  external  angular  process:  this  depression 
contains  the  lachrymal  gland.  Half  an  inch  above  the  lower 
margin  of  the  internal  angular  process,  a  much  smaller  depres- 
sion exists,  occasioned  by  the  tendon  of  the  superior  oblique 
muscle  where  it  plays  upon  its  trochlea.  In  the  orbitary  ridge, 
just  without  the  latter  depression,  is  the  supra-orbitary  foramen 
or  notch,  for  the  passage  of  the  frontal  artery  and  nerve. 

The  internal  margins  of  the  orbitar  processes  are  broad  and 
cellular,  where  they  join  the  ethmoid  bone;  and  at  their  fore 
part  is  seen  a  large  opening  on  each  side  leading  into  the 
frontal  sinus.  These  margins,  in  common  with  the  ethmoid 
bone,  form  two  foramina,  one  anterior,  another  posterior,  and 
called  internal  orbitary;  the  first  transmits  the  internal  nasal 
branch  of  the  ophthalmic  nerve  and  the  anterior  ethmoidal 
artery  and  vein,  the  latter  transmits  the  posterior  ethmoidal 
artery  and  vein.  Externally  and  behind,  the  orbitar  process 
presents  a  broad  triangular  serrated  surface  for  articulating 
with  the  sphenoid  bone. 

The  interior  or  cerebral  face  of  the  os  frontis  is  strongly 
marked  by  depressions  corresponding  with  the  convolutions  of 
the  brain;  on  its  middle  exists  a  vertical  ridge,  becoming  more 
elevated  as  it  approaches  the  ethmoidal  bone.  This  ridge  is 
situated  below,  extends  about  one-half  of  the  length  of  the 
bone,  and  terminates,  above,  in  a  superficial  fossa,  made  by 
the  longitudinal  sinus  of  the  dura  mater;  at  its  lower  extremity 
is  the  foramen  caecum,  common  to  it  and  the  ethmoid  bone, 
and  which  is  occupied  by  a  process  from  the  great  falx  of  the 
dura  mater,  and  also  affords  passage  to  some  very  small  veins, 
which  go  from  the  nostrils  to  the  commencement  of  the  longi- 
tudinal sinus.* 

The  frontal  sinuses  consist  in  one  or  more  large  cells,  placed 
beneath  the  nasal  protuberances.  There  is  a  very  great 
variety  in  their  magnitude  and  extent;  sometimes  they  proceed 
as  far  outwards  as  the  external  angular  process,  and  back- 
wards for  half  an  inch  into  the  orbitar  plates.  In  a  few 
instances  in  the  adult  they  do  not  exist,  but  the  cases  are  very 
uncommon.  The  cells  of  the  opposite  sides  have  a  complete 

*  Portal.  Anat.  Medicalo. 
11* 


126  SKELETON. 

partition.  They  communicate  with  the  cavity  of  the  nose 
through  the  anterior  ethmoidal  cells. 

With  the  exception  of  the  inferior  part,  where  the  processes 
and  sinuses  exist,  the  os  frontis  is  of  a  very  uniform  thickness, 
and  the  diploic  or  cellular  structure  is  found  constantly  be- 
tween its  external  and  internal  faces. 

This  bone  is  united  to  the  parietal,  ethmoidal,  and  sphenoi- 
dal  of  the  cranium;  and  to  several  bones  of  the  face. 


2.  Parietal  Bones,  (Ossa  Parietalia,  Os  Parietaux.) 

These  bones,  it  has  been  stated,  form  the  superior  and  lateral 
parts  of  the  middle  of  the  cranium.  They  are  quadrilateral, 
convex  externally,  and  concave  internally.  Their  external  and 
internal  tables  are  uniformly  separated  by  a  diploic  structure, 
which,  from  being  more  abundant  at  the  superior  part  of  the 
bones,  occasions  there  an  increased  thickness. 

The  external  surface  of  the  parietal  bone  is  raised  about  its 
middle  into  the  parietal  protuberance.  Just  below  this  protu- 
berance is  an  arched,  rough,  broad,  but  slightly  elevated  ridge, 
marking  the  origin  of  the  temporal  fascia  and  muscle,  and 
continuous  with  the  ridge  on  the  side  of  the  frontal  bone. 
The  internal  surface  of  the  bone  is  marked  by  the  convolutions 
of  the  brain ;  there  are  also  a  number  of  furrows  upon  it,  hav- 
ing an  arborescent  arrangement,  and  produced  by  the  ramifi- 
cations of  the  middle  artery  of  the  dura  mater.  These  furrows 
all  proceed  from  two  large  ones  at  the  anterior  arid  at  the  infe- 
rior part  of  the  bone:  not  unfrequently  at  the  latter  point  these 
furrows  are  converted  into  perfect  tubes,  by  the  deposition  of 
bone  all  around  the  arteries.  Of  these  furrows,  the  foremost 
may  be  traced  from  the  greater  wing  of  the  sphenoidal  bone, 
and  running  somewhat  parallel  with  the  anterior  margin  of  the 
parietal;  and  the  other  passing  from  the  squamous  portion  of 
the  temporal,  is  a  little  behind  the  middle  of  the  parietal,  and 
inclines  towards  its  posterior  superior  angle.  The  internal 
face  of  the  parietal  bone  also  presents  an  imperfect  fossa  at  its 
superior  margin,  which  is  completed  by  junction  with  its  fel- 
low, and  accommodates  the  longitudinal  sinus  of  the  dura  ma- 
ter. Near  this  edge  it  is  not  uncommon  to  see  one  or  more 


THE  CRANIUM.  127 

small  irregular  pits  through  the  internal  table,  and  looking 
somewhat  ulcerated :  these  are  formed  by  the  glands  of  Pac- 
chioni,  in  the  dura  mater.  At  the  inferior  posterior  corner  of 
the  bone,  there  is  also  a  fossa,  which  is  made  by  the  lateral 
sinus  of  the  dura  mater. 

The  superior,  posterior,  and  anterior  margins  of  the  parietal 
bone  are  regularly  serrated,  and  nearly  straight.  The  inferior 
margin  is  concave,  presenting  a  thin,  bevelled,  radiated  surface 
before,  for  articulating  with  the  squamous  portion  of  the  tem- 
poral bone:  behind  this  concavity,  the  angle  of  the  bone  is 
truncated  and  serrated,  for  articulating  with  the  angular  por- 
tion of  the  os  temporis.  The  anterior  inferior  angle  is  the 
most  remarkable,  from  its  being  elongated  so  as  to  join  the 
sphenoid  bone  in  the  temporal  fossa. 

A  foramen,  called  parietal,  is  found  at  the  superior  margin 
of  this  bone,  nearer  to  its  posterior  than  to  the  anterior  edge; 
it  transmits  an  artery  between  the  integuments  and  dura  mater, 
and  also  a  vein  from  the  integuments  to  the  longitudinal  sinus. 
M.  Portal  says,  that  in  some  protracted  headaches  this  vein 
swells  considerably;  and  that  he  has  seen  much  good  in  such 
cases,  arise  from  the  application  of  leeches  to  the  part :  he  has 
also  seen,  in  a  child,  its  tumefaction  the  precursor  of  the  pa- 
roxysms of  epilepsy. 

The  parietal  bone  articulates  with  its  fellow,  with  the  fron- 
tal, the  sphenoid,  the  temporal,  and  the  occipital  bones. 


3.  Occipital  Bone,  (Os  Occipitis,  Occipital) 

This  bone  is  quadrilateral,  resembling  a  trapezium.  It  is 
convex  externally,  and  concave  internally;  but  both  of  these 
surfaces  are  much  modified  by  ridges  and  processes.  Its 
thickness  is  also  very  unequal;  though,  Hke  the  other  bones,  it 
has  two  tables,  with  an  intermediate  diploe.  It  is  so  placed  as 
to  form  a  considerable  share  of  the  posterior  and  inferior  pa- 
rietes  of  the  cranium. 

The  foramen  magnum  is  found  in  the  lower  section  of  this 
bone,  and  constitutes  a  very  conspicuous  feature  in  it.  This 


128  SKELETON. 

hole  is  oval,  the  long  diameter  extending  from  before  back- 
wards. Its  anterior  inferior  margin,  on  either  side,  is  furnished 
with  a  condyle,-  for  articulating  with  the  first  vertebra  of 
the  neck.  These  condyles  are  long  eminences  tipped  with 
cartilage,  which  converge  forwards,  so  that  lines  drawn 
through  their  length  would  meet  an  inch  in  front  of  the  fora- 
men magnum;  they  recede  behind:  their  internal  margins  are 
deeper  than  their  external.  The  condition  of  their  articular 
surfaces  is  therefore  such,  that  they  permit  flexion  and  exten- 
sion of  the  head,  but  not  rotation.  The  anterior  edge  of  the 
foramen  is  thicker  than  the  posterior.  This  foramen  transmits 
the  medulla  oblongata,  the  vertebral  arteries  and  veins,  and 
the  spinal  accessory  nerves. 

The  external  surface  of  the  occiput  presents,  half  way  be- 
tween the  foramen  magnum  and  the  upper  angle  of  the  bone, 
the  occipital  protuberance,  from  the  lower  part  of  which  a 
small  vertical  ridge  is  extended  in  the  middle  line  to  that 
foramen.  Into  the  ridge  is  inserted  the  Ligamentum  Nuchae. 
From  either  side  of  the  protuberance  an  arched  ridge  is  ex- 
tended to  the  lateral  angle  of  the  bone ;  it  is  the  superior  semi- 
circular ridge  or  line,  from  which  arise  the  occipito  frontalis 
and  the  trapezius  muscles,  and  into  it  is  inserted  a  part  of  the 
sterno  cleido-mastoideus.  Below  this  about  an  inch  is  the  in- 
ferior semicircular  ridge,  more  protuberant,  but  not  so  dis- 
tinctly marked  in  its  whole  course.  Into  the  inner  space, 
between  the  upper  and  lower  ridges,  is  inserted  the  complexus 
muscle,  and  into  the  outer  space  between  the  same,  the  sple- 
nms  muscle.  The  lower  ridge  is  principally  occupied  by  the 
origin  of  the  superior  oblique  muscle  of  the  neck. 

The  inner  space  between  this  ridge  and  the  great  foramen, 
gives  origin  to  the  rectus  posticus  minor,  and  the  outer  space  to 
the  rectus  posticus  major.  Into  a  small  elevation,  leading  from 
the  outside  of  the  condyle  directly  to  the  margin  of  the  bone, 
is  inserted  the  rectus  capitis  lateralis. 

In  a  depression  behind  each  condyle  is  the  posterior  condy- 
loid  foramen,  which  conducts  a  cervical  vein  to  the  lateral  sinus. 
Passing  through  the  base  of  the  condyle,  and  having  its  orifice 
in  front,  is  the  anterior  condyloid  foramen  for  conducting  the 
hypoglossal  nerve  to  the  toncm*. 


THE  CRANIUM.  129 

That  part  of  the  bone  before  the  condyles  is  the  cuneiform  or 
basilar  process:  the  base  of  which  is  marked  by  depressions  for 
the  insertion  of  the  recti  muscles,  which  are  situated  on  the 
front  of  the  cervical  vertebrae;  and  its  fore  part,  which  is  trun- 
cated at  the  end,  overhangs  the  pharynx,  and  is  placed  against 
the  body  of  the  sphenoid  bone.  The  superior  external  part  of 
the  os  occipitis  is  uniformly  convex,  being  covered  by  the  oc- 
cipito  frontalis. 

The  internal  surface' of  the  os  occipitis  is  strongly  impressed 
by  ridges  and  depressions.  On  that  portion  of  it  behind  the 
great  foramen,  is  a  rectangular  cross,  forming  at  its  centre  a 
large  internal  protuberance.  The  upper  limb  of  the  cross  is 
marked  by  a  fossa  for  the  longitudinal  sinus;  the  two  horizon- 
tal limbs  are  also  marked,  each  by  its  respective  fossa,  which 
receives  the  corresponding  lateral  sinus.  The  right  fossa  is  fre- 
quently the  largest.  The  inferior  vertical  limb  of  the  cross  has 
attached  to  it  the  small  falx  of  the  dura  mater,  and  is  slightly 
depressed  by  a  small  sinus.  The  spaces  between  the  limbs  of 
the  cross  are  much  thinner  than  other  parts  of  the  bone,  and 
present  broad  concavities,  the  two  superior  of  which  receive 
the  posterior  lobes  of  the  cerebrum,  and  the  two  inferior,  the 
lobes  of  the  cerebellum. 

The  superior  face  of  the  cuneiform  process  is  excavated,  lon- 
gitudinally, to  receive  the  medulla  oblongata.  On  each  side  of 
the  foramen  magnum,  a  short  curved  fossa  is  observed,  which 
receives  the  lateral  sinus  just  before  its  exit  from  the  cranium. 

The  two  superior  margins  of  the  occipital  bone  are  regularly 
serrated.  The  inferior  margins  have  each,  in  their  centre,  a 
process  termed  the  jugular  eminence,  in  front  of  which  is  a 
rounded  notch,  forming  a  part  of  the  jugular  fossa,  which  trans- 
mits the  internal  jugular  vein  and  the  eighth  pair  of  nerves. 
The  edge  of  the  bone  above  this  eminence  is  serrated,  but  be- 
low it  is  rather  smooth  and  rounded,  being  parallel  with  the 
temporal  bone,  and  having  an  imperfect  adhesion  to  the  petrous 
part  of  it,  before  the  jugular  fossa.  • 

The  occipital  bone  articulates  above  with  the  parietal,  lateral- 
ly with  the  temporal;  and  in  front  with  the  sphenoid. 


130  SKELETON. 

4.  Temporal  Bones,  (Ossa  Temporum,  Temporaux.) 

These  bones  form  portions  of  the  inferior  lateral  parietes,  and 
of  the  base  of  the  cranium. 

Their  figure  is  very  irregular.  Their  circular  anterior  por- 
tion is  called  squamous :  behind  it  is  the  mastoid,  and  between 
the  others  is  the  petrous. 

The  squamous  portion  is  thinner  than  the  other  bones  of  the 
cranium  that  have  been  described,  from  the  temporal  muscle  and 
its  fascia  covering  it,  so  as  to  afford  sufficient  protection  to  the 
brain.  Its  exterior  surface  is  smooth  and  slightly  convex.  The 
interior  surface  is  formed  into  fossa?  by  the  convolutions  of  the 
brain.  At  the  anterior  inferior  part  of  the  latter  surface,  a 
groove  is  made  by  the  middle  artery  of  the  dura  mater,  imme- 
diately after  it  gets  from  the  foramen  spinale  of  the  sphenoid 
bone  on  its  way  to  the  parietal.  This  groove  bifurcates,  one 
branch  runs  backwards  to  join  the  posterior  groove  of  the  pa- 
rietal bone;  and  the  other  ascends  to  join  the  anterior  groove 
of  the  same,  frequently,  however,  impressing  the  top  of  the 
great  wing  of  the  sphenoid,  just  before  it  reaches  the  parietal. 
The  greater  part  of  the  circumference  of  this  portion  is  sloped 
to  a  sharp  edge,  but  at  the  anterior  inferior  part  it  is  serrated 
and  thicker.  On  the  outside  of  the  latter  is  the  glenoid  cavity, 
for  articulating  with  the  lower  jaw:  the  length  of  it  is  trans- 
verse, with  a  slight  inclination  backwards,  so  that  a  line  drawn 
through  it  would  strike  the  foramen  magnum  occipitis.  The 
anterior  margin  of  this  cavity  is  formed  by  a  tubercle,  on  which 
the  condyle  of  the  lower  jaw  rises  when  the  mouth  is  widely 
opened.  The  outer  margin  of  the  glenoid  cavity  is  formed  by 
the  root  of  the  zygomatic  process.  The  zygomatic  process  has 
a  broad  horizontal  root,  from  which  it  extends  outwardly,  and 
then  diminishing,  runs  forwards  to  join  the  malar  bone.  Pos- 
terior to  the  root  of  the  zygomatic  process,  a  small  vertical 
groove  may  be  seen  occasionally,  made  by  the  middle  tempo- 
ral artery. 

The  mastoid  portion  of  the  temporal  bone,  is  thick  and  cel- 
lular. Its  upper  part  forms  an  angle,  which  is  received  between 
the  parietal  and  occipital  bones:  both  margins  of  this  angle  are 


THE  CRANIUM.  131 

serrated.  Below,  is  the  mastoid  process,  a  large  conical  pro- 
jection eight  lines  long,  into  which  are  inserted  the  sterno-mas- 
toid,  and  trachelo-mastoid  muscles.  At  the  inner  side  of  its 
base  is  a  fossa  affording  origin  to  the  digastric  muscle.  The 
inner  face  of  the  mastoid  portion  is  marked  by  a  deep  large  fossa 
for  the  lateral  sinus  of  the  dura  mater.  In  the  posterior  part  of 
the  suture,  uniting  the  mastoid  portion  and  the  occipital  hone, 
or  in  the  former  bone  near  the  suture,  is  the  mastoid  foramen, 
for  conducting  a  vein  from  the  integuments  into  the  lateral 
sinus. 

The  cells  in  the  mastoid  bone  are  large  and  numerous,  and 
obtain  the  name  of  sinuses;  they  communicate  with  the  tym- 
panum by  one  large  orifice.  On  the  outer  side  of  these  sinuses 
a  thin  diploic  structure  is  observable  in  some  heads. 

The  petrous  portion  of  the  temporal  bone  is  a  triangular  py- 
ramid, arising  by  a  broad  base  from  the  inner  side  of  the  mas- 
toid and  squamous  portions.  It  is  fixed  obliquely  forwards,  be- 
tween the  sphenoid  and  occipital  bones.  Its  anterior  surface  is 
marked  by  the  convolutions  of  the  brain.  Near  the  centre  of 
this  surface,  and  having  a  little  superficial  furrow  leading  to 
it,  is  a  small  foramen  called  the  Hiatus  Fallopii,  through  which 
passes  the  Vidian  nerve.  The  posterior  surface  of  the  petrous 
portion  presents  a  large  foramen,  the  meatus  auditorius  internus, 
through  which  pass  the  seventh  or  the  auditory  and  the  facial 
nerve.  Half  an  inch  behind  this  orifice,  is  a  very  small  one, 
overhung  by  a  flat  shelf  of  bone;  this  is  said  to  be  the  aqueduct 
of  the  vestibule.  Just  above  the  meatus  auditorius  internus  is 
a  foramen  more  patulous  than  the  aqueduct,  for  transmitting 
small  blood  vessels. 

In  the  base  of  the  petrous  portion,  between  the  mastoid  and 
zygomatic  processes,  is  the  meatus  auditorius  externus,  a  large 
opening  conducting  to  the  tympanum.  It  is  oval,  about  half  an 
inch  deep,  and  varies  much  in  its  size  in  different  subjects:  its 
margin  is  called  the  auditory  process,  the  lower  part  of  which 
is  very  rough,  for  attaching  the  cartilage  of  the  external  ear. 

The  lower  surface  of  the  petrous  bone  is  exceedingly  irregu- 
lar. Immediately  below  the  meatus  externus,  is  a  depression 


1 32  SKELETON. 

which  seems  like  a  part  of  the  glenoid  cavity,  and  is  improper- 
ly considered  as  such  by  anatomists,  inasmuch  as  it  does  not 
form  a  portion  of  the  articular  surface  for  the  lower  jaw,  but 
simply  allows  room  for  its  motions,  the  parts  which  it  contains 
(consisting  of  vessels,  and  a  portion  of  the  parotid  gland)  being 
pressed  back  when  the  jaw  opens.  Between  this  cavity  and 
the  glenoid  is  the  glenoidal  fissure,  separating  the  petrous  from 
the  squamous  bone.  In  this  fissure,  leading  to  the  tympanum, 
is  a  foramen  which  contains  the  processus  gracilis  of  the  mal- 
leus with  its  muscle,  and  the  chorda  tympani.  The  posterior 
margin  of  the  depression  just  alluded  to  in  the  petrous  bone,  is 
made  by  a  long  rough  ridge,  called  processus  vaginalis;  just 
behind  which,  and  partially  surrounded  by  it,  is  the  styloid  pro- 
cess. The  styloid  process  is  round,  tapering,  and  an  inch  and 
a  half  long ;  but  frequently  absent  in  prepared  skulls,  from  acci- 
dental fracture  and  from  being  in  a  cartilaginous  state.  From 
it  arise  the  styloid  muscles. 

Behind  the  root  of  the  styloid  process,  is  the  stylo  mastoid 
foramen,  which  transmits  the  portio  dura  or  facial  nerve  to  the 
face.  Just  within  the  styloid  process  and  the  foramen  is  a  deep 
depression,  called  jugular  fossa,  large  enough  to  receive  the 
tip  of  the  little  finger.  The  fossa,  along  with  a  corresponding 
one  in  the  os  occipitis,  is  occupied  by  the  internal  jugular  vein 
and  the  eighth  pair  of  nerves.  Immediately  before  the  lower 
end  of  this  fossa  is  the  foramen  caroticum,  being  the  lower  ori- 
fice of  a  crooked  canal,  which  terminates  at  the  apex  of  the 
petrous  bone,  and  transmits  the  carotid  artery  and  the  upper 
extremity  of  the  sympathetic  nerve.  At  the  inner  side  of  the 
carotid  canal,  a  superficial  serrated  groove  is  perceived,  which 
receives  the  adjoining  edge  of  the  occipital  bone.  Just  in  ad- 
vance of  the  inner  part  of  the  jugular  fossa  is  a  small  spine  of 
bone,  at  the  foot  of  which  is  a  pit,  containing  the  orifice  of  the 
supposed  aqueduct  of  the  cochlea.  The  spine  separates  the 
eighth  pair  of  nerves  from  the  internal  jugular  vein. 

In  the  angle  between  the  squamous  and  petrous  bones,  within 
the  glenoid  foramen,  is  the  orifice  of  the  Eustachian  tube.  The 
tube  is  divided  longitudinally,  by  a  bony  partition.  The  upper 
division  contains  the  tensor  tympani  muscle. 

A  small  groove  exists  along  the  superior  angle  of  the  petrous 


THE  CRANIUM.  •          1 33 

bone,  and  another  along  the  inferior  angle,  adjoining  the  basilar 
process  of  the  occipital  bone,  and  formed  in  part  by  it :  they 
are  made  by  the  superior  and  inferior  petrous  sinuses. 

The  temporal  bone  articulates  with  the  occipital,  the  parie- 
tal, the  sphenoid,  and  the  malar. 


5.  Sphenoid  Bone,  (Os  Sphenoides,  Sphenoide.) 

The  sphenoid  is  a  symmetrical,  but  very  irregular  bone, 
placed  transversely  in  the  middle  of  the  base  of  the  cranium. 

It  consists  of  a  cuboidal  body  in  the  centre,  of  a  very  large 
process  called  the  great  wing,  and  spreading  laterally  to  a  con- 
siderable distance  on  either  side  of  the  body,  and  it  has,  also, 
a  number  of  angular  margins  and  additional  processes  about  it. 

In  regard  to  the  body  of  the  sphenoid  bone,  from  its  upper 
anterior  part  arise,  one  on  each  side,  the  apophyses  of  Ingras- 
sias,  or  the  little  wings.  These  wings  have  a  broad  horizontal 
base,  and  extending  themselves  outwardly,  terminate  in  a  sharp 
point.  Their  anterior  edge  is  serrated  for  articulating  with 
the  os  frontis :  the  posterior  edge  is  smooth.  Between  the  two 
wings,  in  front,  is  a  prominence  united  to  the  ethmoid  bone. 
The  base  of  the  wing  is  perforated  by  the  foramen  opticum, 
for  transmitting  the  optic  nerve  with  the  ophthalmic  artery. 
Below  and  behind  this  foramen,  the  little  wing  terminates  in  a 
point,  called  the  anterior  clinoid  process.  Between  the  fora- 
mina optica  is  a  ridge  of  bone,  sometimes  called  processus  oli- 
varis,  and  just  above  the  ridge  a  groove,  made  by  the  optic 
nerves  where  they  unite.  Behind  the  ridge  is  a  depression, 
the  Sella  Turcica,  for  containing  the  pituitary  gland.  This 
depression  is  bounded  behind  by  a  very  elevated  transverse 
ridge,  called  the  posterior  clinoid  process.  At  either  extremi- 
ty of  the  base  of  the  latter,  a  groove  (sulcus  caroticus)  is  made 
by  the  carotid  artery,  which  groove  may  be  traced  indistinctly 
under  the  anterior  clinoid  process,  where  it  forms  a  notch,  and 
sometimes  a  foramen. 

The  posterior  face  of  the  body  of  the  sphenoid  bone,  presents 
a  flat  surface  for  articulating  with  the  cuneiform  process  of  the 
occipital.  Most  frequently,  in  the  adult,  the  bones  are  anchy- 
losed  at  this  junction.  The  inferior  part  of  the  body  of  the 
sphenoid  presents  a  rising,  in  its  middle,  called  the  sphenoidal 
VOL.  I.— 12 


1 34  SKELETON. 

or  azygous  process,  for  articulation  with  the  vomer,  and  with 
the  nasal  septum  of  the  ethmoid.  On  each  side  of  this  process, 
in  front,  is  the  orifice  of  the  sphenoidal  cell.  These  cells  con- 
sist, most  commonly,  of  one  on  each  side,  and  are  separated 
by  a  bony  partition.  In  the  very  young  bone  they  are  not 
formed.  The  body  of  the  sphenoid  undergoes  so  many  changes 
between  early  infancy  and  adult  life,  by  the  conversion  of  its 
diploic  structure  into  sinuses  or  cells,  and  is  also  so  much  mo- 
dified in  different  individuals,  that  a  general  description  of  it 
will  not  answer  for  all  specimens. 

The  two  great  wings  arise  from  the  sides  of  the  body  of  the 
sphenoid,  by  a  small  irregular  base.  From  their  lower  part  pro- 
ject downvvards,on  either  side,  the  two  pterygoid  processes  called 
external  and  internal.  These  processes  have  a  common  base, 
are  partially  separated  behind  by  a  groove  called  pterygoid  fossa, 
and  below  by  a  notch.  The  internal  is  the  longest,  and  is  termi- 
nated by  a  hook,  on  the  outer  side  of  which  is  a  trochlea  made 
by  the  tendon  of  the  circumflexus  muscle.  The  external  ptery- 
goid process  is  the  broadest.  By  applying  together  the  temporal 
and  sphenoid  bones,  a  groove,  common  to  the  two,  leading  to 
the  Eustachian  tube,  will  be  seen.  This  groove  is  continued 
obliquely  across  the  root  of  the  internal  pterygoid  process,  and 
indicates  the  course  of  the  cartilaginous  portion  of  the  Eusta- 
chian tube.  The  internal  pterygoid  process  sends  out  from  its 
base  a  small  shelf  of  bone,  separated  by  a  fissure  from  the  un- 
der part  of  the  body  of  the  sphenoid.  The  posterior  edge  of 
the  vomer  rests  against  this  projection.  The  fissure  is  filled  up 
in  advanced  life. 

The  great  wings  of  the  sphenoid  bone  present  three  faces. 
One  is  anterior,  and  called  orbital,  from  its  forming  a  part  of  the 
orbit;  another  is  external,  and  called  temporal;  and  the  third  is 
towards  the  brain,  and  forms  a  considerable  part  of  the  fossa 
for  containing  its  middle  lobe.  The  orbital  face  is  square  and 
slightly  concave.  The  temporal  face  is  an  oblong  concavity,  at 
the  lower  part  of  which  is  a  triangular  process,  giving  an  origin 
to  the  external  pterygoid  muscle.  The  cerebral  face  is  concave 
and  marked  by  the  convolutions  of  the  brain,  as  well  as  by  a 
furrow  made  by  the  principal  trunk  of  the  great  artery  of  the 
dura  mater  as  it  passes  from  the  temporal  bone  to  the  temporal 
angle  of  the  parietal.  The  inferior  portion  of  the  great  wing  is 


THE  CRANIUM.  135 

elongated  backwards  into  a  horizontal  angle,  called  the  spinous 
process,  which  is  fixed  between  the  petrous  and  squamous  portions 
of  the  temporal  bone.  From  the  point  of  the  spinous  process  pro- 
jects downwards  the  styloid  process.  The  great  wing  presents 
a  triangular  serrated  surface  above,  at  its  outer  end,  by  which 
it  articulates  with  the  osfrontis;  just  below  this,  in  front,  is  a  short 
serrated  edge,  by  which  it  articulates  with  the  malar  bone;  and 
externally, is  a  semicircular  serrated  edge,  by  which  it  articulates 
with  the  squamous  portion  of  the  temporal  bone.  The  tip  of  the 
large  wing  generally  articulates  also  with  the  parietal  bone. 

Between  the  apophysis  of  Ingrassias  and  the  greater  wing  is 
the  foramen  sphenoidale,  called  also  foramen  lacerum  superius  of 
the  orbit.  It  is  broad  near  the  body  of  the  bone,  and  becomes  a 
mere  slit  at  the  extremity  of  the  little  wing.  Through  it  pass 
the  third,  fourth,  the  first  branch  of  the  fifth,  and  the  sixth  pair 
of  nerves.  Two  lines  below  the  base  of  this  hole  is  the  foramen 
rotundum,  for  transmitting  the  second  branch  of  the  fifth  pair  of 
nerves.  Eight  lines,  or  thereabouts,  behind  the  foramen  rotun- 
dum, is  the  foramen  ovale,  for  transmitting  the  third  branch  of 
the  fifth  pair  of  nerves.  Two  lines  behind  the  foramen  ovale  is 
the  foramen  spinaie,  for  transmitting  the  middle  artery  of  the 
dura  mater.  In  the  under  part  of  the  bone,  and  passing  through 
the  root  of  the  pterygoid  processes,  is  the  foramen  pterygoideum, 
for  transmitting  the  pterygoid  nerve;  it  being  a  recurrent  branch 
of  the  second  branch  of  the  fifth  pair  of  nerves. 

The  sphenoid*  bone  articulates  above  and  in  front  with  the 
vomer,  the  frontal,  ethtnoidal,  malar,  and  parietal  bones  :  late- 
rally with  the  temporal,  behind  with  the  occipital,  and  by  its 
pterygoid  processes  with  the  palate  bones. 

6.  Ethmoid  Bone,  (Os  Elhmoides,  Ethmoide.) 

This  bone  is  placed  between  the  orbitar  processes  of  the  os 
frontis,  and,  as  has  been  stated,  fills  the  vacuity  between  them. 
It  is  cuboidal,  extremely  cellular,  and  light. 

The  horizontal  portion  between  the  orbitar  processes  is  the 

*  This  bone  is,  by  some  anatomists,  described  in  common  with  the  os  occipitis, 
&  the  osbasilare,  in  consequence  of  their  early  junction  into  a  single  piece. 


136  SKELETON. 

cribriform  plate  called  so  from  its  numerous  perforations.  This 
is  divided,  longitudinally,  above  and  below,  by  a  vertical  pro- 
cess ;  and  from  the  under  surface  on  each  side,  is  suspended  the 
cellular  portion. 

The  vertical  process  on  the  superior  face  of  the  cribriform 
plate  is  the  crista  galli,  which  extends  sometimes  from  the  back 
to  the  front  of  this  plate,  and  is  thickest  in  the  middle.  The  com- 
mencement of  the  great  falx  arises  from  it,  and  occasionally  it 
contains  a  cell  or  sinus  opening  into  the  nose.  Between  the  front 
of  the  crista  galli  and  ihe  os  frontis,  is  the  foramen  crecum,  al- 
ready described.  On  either  side  of  the  crista  galli  the  cribriform 
plate  is  depressed  into  a  gutter  for  holding  the  bulb  of  the  olfac- 
tory nerve,  and  is  perforated  with  many  holes  for  transmitting 
its  ramifications.  The  most  anterior  foramen  on  each  side  is 
oval,  and  transmits  to  the  nose  the  internal  nasal  nerve,  after  it 
has  got  into  the  cranium  through  the  anterior  internal  orbitar 
foramen.  The  margins  of  the  cribriform  plate  show  many  im- 
perfect cells,  which  are  completed  by  joining  their  congeners 
in  the  margins  of  the  orbitar  processes  of  the  os  frontis. 

The  vertical  process  below  the  cribriform  plate  is  called 
nasal  lamella.  It  generally  divides  the  nostrils  equally,  but  is 
occasionally  inclined  to  one  side.  It  joins  below,  to  the  vomer 
and  the  cartilaginous  septum  of  the  nose ;  in  front  is  in  contact 
with  the  nasal  spine  of  the  frontal  bone  and  with  the  nasal 
bones;  and  behind,  with  the  azygous  process  of  the  sphenoid. 

Each  cellular  portion  of  the  ethmoid  forms,  by  its  exterior,  a 
part  of  the  orbit  of  the  eye,  which  surface  is  called  os  planum. 
The  internal  or  nasal  face  forms  part  of  the  nostril.  The  fore 
part  of  this  face  is  flat,  but,  posteriorly,  in  its  middle,  is  a  deep 
sulcus,  called  the  superior  meatus  of  the  nose.  The  upper  tur- 
binated  bone,  a  small  scroll,  constitutes  the  upper  margin  of 
this  meatus.  The  inferior  internal  margin  of  the  cellular  por- 
tion of  the  ethmoid,  is  formed  by  another  scroll  of  bone,  run- 
ning its  whole  length.  This  is  the  middle  turbinated  bone. 
Moreover,  from  the  inferior  margin  of  the  cellular  portion,  one 
or  more  laminse,  of  an  irregular  form,  project  so  as  to  diminish 
the  opening  into  the  upper  maxillary  sinus. 


THE  CRANIUM.  137 

The  cells  in  the  ethmoid  bone  are  numerous  and  large,  the 
posterior  ones  discharge,  by  one  or  more  orifices,  into  the  upper 
meatus.  The  anterior  discharge  into  the  middle  meatus  of  the 
nose  by  several  orifices,  concealed  by  the  middle  turbinated 
bone.  The  most  anterior  of  these  cells  is  funnel-shaped,  and 
joining  the  frontal  sinus,  conducts  the  discharge  of  the  latter 
into  the  nose. 

In  children  of  from  three  to  eight  years  of  age,  there  is  at- 
tached to  the  posterior  part  of  each  cellular  portion  of  the  eth- 
moid, a  triangular  hollow  pyramid,  consisting  of  a  single  cell. 
This  pyramid  arises,  not  only  from  the  cellular  portion,  but  also 
from  the  posterior  margin  of  the  cribriform  plate,  and  of  the 
nasal  lamella,  by  which  it  gains  a  large  and  secure  base.  The 
processus  azygos  of  the  sphenoid  bone  is  received  between  the 
two  pyramids.  In  the  base  of  the  pyramid,  communicating 
with  the  nose,  is  a  foramen,  which  is  known  in  adult  life  as  the 
orifice  of  the  sphenoidal  sinus.  The  pyramid,  towards  puberty, 
becomes  a  part  of  the  sphenoidal  bone,  and  then  detaches  it- 
self, by  a  suture  at  its  base,  from  the  ethmoidal.  As  life  ad- 
vances it  is  greatly  developed,  no  indication  of  its  original 
condition  remains,  and  it  becomes  fairly  the  sphenoidal  cell; 
singularly  differing  in  shape  from  what  it  was  in  the  begin- 
ning.* 

Being  put  upon  the  investigation  of  this  pyramid  by  the  late 
Professor  Wistar,  with  the  view  of  ascertaining  its  different 
phases  of  development,  it  has  occurred  to  me  to  see  it  in  every 
stage,  from  that  of  a  simple  triangular  lamina,  arising  from 
the  posterior  margin  of  the  cribriform  plate,  to  the  perfect  hol- 
low pyramidal  slate.  The  preceding  anatomists  describe  it 
but  imperfectly;  it  remained  for  that  distinguished  individual 
to  elucidate  its  real  history. 

Several  of  the  articulations  of  the  ethmoid  have  been  men- 
tioned; the  remainder  will  be  introduced  with  the  bones  of  the 
face. 

*  Wistar's  Anatomy,  vol.  i.  p.  31,  3d  edit. 


136  SKELETON. 

cribriform  plate  called  so  from  its  numerous  perforations.  This 
is  divided,  longitudinally,  above  and  below,  by  a  vertical  pro- 
cess ;  and  from  the  under  surface  on  each  side,  is  suspended  the 
cellular  portion. 

The  vertical  process  on  the  superior  face  of  the  cribriform 
plate  is  the  crista  galli,  which  extends  sometimes  from  the  back 
to  the  front  of  this  plate,  and  is  thickest  in  the  middle.  The  com- 
mencement of  the  great  falx  arises  from  it,  and  occasionally  it 
contains  a  cell  or  sinus  opening  into  the  nose.  Between  the  front 
of  the  crista  galli  and  ihe  os  frontis,  is  the  foramen  ccecum,  al- 
ready described.  On  either  side  of  the  crista  galli  the  cribriform 
plate  is  depressed  into  a  gutter  for  holding  the  bulb  of  the  olfac- 
tory nerve,  and  is  perforated  with  many  holes  for  transmitting 
its  ramifications.  The  most  anterior  foramen  on  each  side  is 
oval,  and  transmits  to  the  nose  the  internal  nasal  nerve,  after  it 
has  got  into  the  cranium  through  the  anterior  internal  orbitar 
foramen.  The  margins  of  the  cribriform  plate  show  many  im- 
perfect cells,  which  are  completed  by  joining  their  congeners 
in  the  margins  of  the  orbitar  processes  of  the  os  frontis. 

The  vertical  process  below  the  cribriform  plate  is  called 
nasal  lamella.  It  generally  divides  the  nostrils  equally,  but  is 
occasionally  inclined  to  one  side.  It  joins  below,  to  the  vomer 
and  the  cartilaginous  septum  of  the  nose;  in  front  is  in  contact 
with  the  nasal  spine  of  the  frontal  bone  and  with  the  nasal 
bones;  and  behind,  with  the  azygous  process  of  the  sphenoid. 

Each  cellular  portion  of  the  ethmoid  forms,  by  its  exterior,  a 
part  of  the  orbit  of  the  eye,  which  surface  is  called  os  planum. 
The  internal  or  nasal  face  forms  part  of  the  nostril.  The  fore 
part  of  this  face  is  flat,  but,  posteriorly,  in  its  middle,  is  a  deep 
sulcus,  called  the  superior  mealus  of  the  nose.  The  upper  tur- 
binated  bone,  a  small  scroll,  constitutes  the  upper  margin  of 
this  meatus.  The  inferior  internal  margin  of  the  cellular  por- 
tion of  the  ethmoid,  is  formed  by  another  scroll  of  bone,  run- 
ning its  whole  length.  This  is  the  middle  turbinated  bone. 
Moreover,  from  the  inferior  margin  of  the  cellular  portion,  one 
or  more  laminae,  of  an  irregular  form,  project  so  as  to  diminish 
the  opening  into  the  upper  maxillary  sinus. 


THE  CRANIUM.  137 

The  cells  in  the  ethmoid  bone  are  numerous  and  large,  the 
posterior  ones  discharge,  by  one  or  more  orifices,  into  the  upper 
nveatus.  The  anterior  discharge  into  the  middle  meatus  of  the 
nose  by  several  orifices,  concealed  by  the  middle  turbinated 
bone.  The  most  anterior  of  these  cells  is  funnel-shaped,  and 
joining  the  frontal  sinus,  conducts  the  discharge  of  the  latter 
into  the  nose. 

In  children  of  from  three  to  eight  years  of  age,  there  is  at- 
tached to  the  posterior  part  of  each  cellular  portion  of  the  eth- 
moid, a  triangular  hollow  pyramid,  consisting  of  a  single  cell. 
This  pyramid  arises,  not  only  from  the  cellular  portion,  but  also 
from  the  posterior  margin  of  the  cribriform  plate,  and  of  the 
nasal  lamella,  by  which  it  gains  a  large  and  secure  base.  The 
processus  azygos  of  the  sphenoid  bone  is  received  between  the 
two  pyramids.  In  the  base  of  the  pyramid,  communicating 
with  the  nose,  is  a  foramen,  which  is  known  in  adult  life  as  the 
orifice  of  the  sphenoidal  sinus.  The  pyramid,  towards  puberty, 
becomes  a  part  of  the  sphenoidal  bone,  and  then  detaches  it- 
self, by  a  suture  at  its  base,  from  the  ethmoidal.  As  life  ad- 
vances it  is  greatly  developed,  no  indication  of  its  original 
condition  remains,  and  it  becomes  fairly  the  sphenoidal  cell; 
singularly  differing  in  shape  from  what  it  was  in  the  begin- 
ning.* 

Being  put  upon  the  investigation  of  this  pyramid  by  the  late 
Professor  Wistar,  with  the  view  of  ascertaining  its  different 
phases  of  development,  it  has  occurred  to  me  to  see  it  in  every 
stage,  from  that  of  a  sample  triangular  lamina,  arising  from 
the  posterior  margin  of  the  cribriform  plate,  to  the  perfect  hol- 
low pyramidal  state.  The  preceding  anatomists  describe  it 
but  imperfectly;  it  remained  for  that  distinguished  individual 
to  elucidate  its  real  history. 

Several  of  the  articulations  of  the  ethmoid  have  been  men- 
tioned; the  remainder  will  be  introduced  with  the  bones  of  the 
face. 

*  Wistar's  Anatomy,  vol.  i.  p.  31,  3d  edit. 

ft* 


140  SKELETON. 

the  nerve  of  the  molar  teeth  to  their  roots,  and  a  similar  canal  is 
seen  in  front  of  the  antrum,  for  the  nerves  of  the  front  teeth. 
The  nerves,  in  both  instances,  come  from  the  infra  orbitary. 
The  nerves,  till  they  begin  to  divide  into  filaments,  are  between 
the  lining  membrane  and  the  antrum,  but  afterwards  they  make 
complete  canals  in  the  alveolar  processes.  The  antrum  fre- 
quently communicates  with  the  frontal  sinus,  through  the  ante- 
rior ethmoidal  cells,  which  circumstance  is  omitted  by  most 
anatomists. 

This  bone  is  articulated  with  the  frontal,  nasal,  unguiform, 
malar,  and. ethmoid,  above;  to  the  palate  bone  behind;  to  its 
fellow,  and  to  the  vomer,  at  its  middle;  and  to  the  inferior 
spongy  bone  by  its  nasal  surface. 

2.  Palate  Bones,  (Ossa  Palati,  Palatins.) 

The  palate  bones,  two  in  number,  are  placed  at  the  back 
part  of  the  superior  maxillary,  between  them  and  the  pterygoid 
processes  of  the  sphenoid. 

For  descriptive  purposes  they  may  be  divided  into  three 
portions — the  horizontal  or  palate  plate,  the  vertical  or  nasal 
plate,  and  the  orbitar  or  oblique  plate,  placed  at  the  upper  ex- 
tremity of  the  latter. 

The  palate  plate  is  in  the  same  line  with  the  palate  process 
of  the  superior  maxillary  bone,  and  supplies  the  deficiency 
caused  by  its  abrupt  termination.  It  is  square.  The  inferior 
surface  is  flat,  but  rough  for  the  attachment  of  the  lining  mem- 
brane of  the  mouth.  The  superior  surface  is  concave,  and 
forms  about  one-third  of  the  bottom  of  the  nose.  The  anterior 
margin  is  serrated  where  it  articulates  with  the  palate  process 
of  the  maxillare  superius.  The  posterior  margin  is  thin  and 
crescentic.  The  internal  extremity  of  the  crescent  is  elon- 
gated into  a  point,  from  which  arises  the  azygos  uvulae  muscle. 
The  internal  margin  of  the  palate  plate  is  thick  and  serrated 
for  articulating  with  its  fellow,  the  upper  edge  of  it  being  turn- 
ed upwards  to  join  the  vomer.  The  exterior  edge  touches  the 
internal  side  of  the  maxillare  superius,  and  from  it  arises  the 
nasal  plate. 


THE  FACE.  141 

The  nasal  plate  forms  the  posterior  external  part  of  the  nos- 
tril, and  is  much  .thinner  than  the  palate  plate.  Its  side  next 
the  nose  is  slightly  concave,  and  is  divided  into  two  unequal 
surfaces,  of  which  the  lower  is  the  smallest,  by  a  transverse 
ridge,  that  receives  the  posterior  extremity  of  the  lower  turbi- 
nated  or  spongy  bone.  The  external  face  is  in  contact  with 
the  internal  face  of  the  maxillary  bone,  and  presents  a  surface 
corresponding  with  it.  The  nasal  plate  of  the  palate  bone 
diminishes  the  opening  into  the  Antrum  Highmorianum  by 
overlapping  it  behind.  Backwards  it  joins  the  pterygoid  pro- 
cess of  the  sphenoid  bone,  and  overlaps  its  anterior  internal 
surface. 

At  the  inferior  and  posterior  part  of  the  nasal  plate,  where 
the  crescentic  edge  of  the  palate  plate  joins  it,  the  palate  bone 
is  extended  into  a  triangular  process,  called  the  pterygoid. 
This  process,  on  its  posterior  surface,  presents  three  grooves, 
the  internal  of  which  receives  the  internal  pterygoid  process 
of  the  sphenoid  bone,  and  the  external  groove  receives  the  ex- 
ternal pterygoid  process  of  the  same  bone.  The  middle  fossa 
has  its  surface  continuous  with  the  pterygoid  fossa  of  the  sphe- 
noid bone,  and  may  be  seen,  in  the  articulated  head,  to  contri- 
bute to  this  fossa.  The  anterior  surface  of  the  pterygoid 
process  of  the  palate  bone  presents  a  small  serrated  tuberosity, 
which  is  received  into  a  corresponding  concavity  on  the  pos- 
terior surface  of  the  maxillary  bone,  and  contributes  to  the 
firmer  junction  of  the  two. 

On  the  external  surface  of  the  nasal  plate,  between  it  and 
the  base  of  the  pterygoid  process,  a  vertical  groove  is  formed, 
which  is  converted  into  a  complete  canal  by  the  maxillary 
bone.  The  lower  orifice  of  this  canal  is  near  the  posterior 
margin  of  the  palate.  It  is  called  the  posterior  palatine  fora- 
men, and  transmits  the  palatine  nerve  and  artery  to  the  soft 
palate.  Immediately  behind  this  canal  there  is,  not  unfre- 
quently,  a  smaller  one,  running  through  the  base  of  the  ptery- 
goid process  of  the  palate  bone,  and  transmitting  a  filament  of 
the  same  nerve  to  the  palate. 

The  upper  extremity  of  the  nasal  plate  is  formed  by  two 
processes,  one  in  front  and  the  other  behind,  separated  either 


14»  SKELETON. 

by  a  round  notch  or  a  foramen.  The  posterior  of  the  two, 
called  also  pterygoid  apophysis,  is  inclined  over  towards  the 
cavity  of  the  nose.  It  is  thin,  and  fits  upon  the  under  surface 
of  the  body  of  the  sphenoid  bone,  and  upon  the  inner  surface 
of  the  internal  base  of  the  pterygoid  process  of  the  same.  Its 
upper  edge  touches  the  base  of  the  vomer.  The  anterior  pro- 
cess is  the  orbitar  portion  of  the  palate  bone. 

The  orbitar  portion  or  plate  is  longer  than  the  pterygoid 
apophysis,  and  is  hollow  and  very  irregular.  It  may  be  seen 
in  the  posterior  part  of  the  orbit  wedged  in  between  the  eth- 
moid and  maxillary  bone.  The  portion  of  it  which  is  there 
seen,  is  the  orbital  face,  and  is  triangular.  On  the  side  of  the 
ethmoid  bone  its  cells  are  seen,  which  are  completed  by  their 
contiguity  to  the  ethmoid  and  sphenoid.  The  cells,  in  young 
subjects,  are  not  always  to  be  met  with.  The  posterior  face 
of  the  orbitar  portion  is  winding  and  looks  towards  the  zygo- 
matic  fossa. 

The  notch  between  the  orbitar  portion  and  the  pterygoid 
apophysis  is  converted  into  a  foramen,  by  that  part  of  the 
body  of  the  sphenoid  bone  which  is  immediately  below  the 
opening  of  the  sphenoid  cell.  Through  this  foramen,  called 
spheno-palatine,  pass  the  lateral  nasal  nerve,  the  spheno-pala- 
tine  artery  and  vein. 

This  bone  can  scarcely  be  studied  advantageously  except  in 
the  separated  head.  A  single  application  of  it  to  the  maxillary, 
will  then  show  how  it  extends  from  the  palate  of  the  mouth  to 
the  orbit  of  the  eye;  and  how  it  is  the  connecting  bone  be- 
tween the  maxillary  bone  and  the  pterygoid  process  of  the 
sphenoid. 

The  palate  bone  articulates  with  six  others.  With  the  up- 
per maxillary,  the  sphenoid,  the  ethmoid,  the  inferior  spongy, 
the  vomer,  and  with  its  fellow.  The  places  of  junction  have 
been  pointed  out  in  the  description  of  the  bone. 

3.  Nasal  Bones,  (Ossa  Nasi,  Os  du  Nez.) 
The  ossa  nasi,  two  in  number,  fill  up  the  vacancy  between 


THE  FACE.  143 

the  nasal  processes  of  the  superior  maxillary  bones.  They  are 
oblong  and  of  a  dense  compact  structure,  being  so  applied  to 
each  other  as  to  form  a  strong  arch  called  the  bridge  of  the 
nose,  which  is  farther  sustained  by  the  nasal  spine  and  the 
continuous  oblique  serrated  surface  of  the  os  frontis. 

The  ossa  nasi  are  thick  and  serrated  at  their  upper  margins; 
below,  they  are  thin  and  irregular.  The  surfaces  by  which 
they  unite  with  each  other  are  broad,  having  their  edges  raised 
where  they  join  the  nasal  lamella  of  the  ethmoid  bone.  The 
edge  by  which  they  join  the  nasal  process  of  the  upper  maxil- 
lary bone  is  concave;  the  upper  part  of  this  edge  is  overlapped 
bv  the  nasal  process,  but  the  lower  part  of  it  overlaps  the  na- 
sal process. 

On  the  posterior  face  of  the  os  nasi  is  to  be  seen  a  small 
longitudinal  groove,  formed  by  the  internal  nasal  branch  of  the 
ophthalmic  nerve,  which  nerve  penetrates  the  foramen  orbitale 
anterius  and  the  cribriform  plate  of  the  ethmoid  bone. 

The  ossa  nasi  articulate  with  each  other  in  front,  with  the 
nasal  processes  of  the  upper  maxillary  behind,  with  the  septum 
narium  where  they  are  in  contact  with  one  another,  and  with 
the  os  frontis  above. 


4.  Unguiform  Bones,  (Ossa  Ungues,  Os  Lacrymaux.) 

The  unguiforrn  is  a  very  small  thin  bone,  "placed  at  the  in- 
ternal side  of  the  orbit,  between  the  nasal  process  of  the  upper 
maxillary  and  the  os  planum  of  the  ethmoid.  Its  orbitar  sur- 
face is  divided  into  a  face  which  is  in  a  line  with  that  of  the 
os  planum,  and  into  an  oblong  vertical  concavity,  continuous 
with  the  concavity  on  the  posterior  surface  of  the  nasal  pro- 
cess, for  lodging  the  lachrymal  sac.  Its  inferior  anterior  cor- 
ner is  elongated  into  the  nose,  so  as  to  join  with  a  process  of 
the  inferior  turbinated  bone,  whereby  the  ductus  ad  nasum  is 
rendered  a  complete  bony  canal. 

This  bone  lies  on  the  orbitar  side  of  the  most  anterior  eth- 
moid cells,  and  completes  them  in  that  direction. 

An  important  variety  in  the  structure  of  this  part  of  the  or- 
bit occasionally  occurs,  in  which  the  whole  fossa  for  lodging 


1 44  SKELETON. 

the  lachrymal  sac,  is  formed  by  the  unusual  breadth  of  the  na- 
sal process  of  the  upper  maxillary  bone.  In  this  case,  the 
only  part  of  the  os  unguis  which  exists,  is  that  in  the  same  line 
with  the  os  planum.  Several  examples  have  come  under  my 
own  notice.  Duverney  has  also  mentioned  it.  Sometimes  it 
is  entirely  wanting,  in  which  case  the  os  planum  joins  the  na- 
sal process.*  A  variety  still  more  uncommon  is  mentioned  by 
Verheyen,  where  the  lachrymal  fossa  is  formed  exclusively  by 
the  os  unguis. 

This  bone  articulates  very  loosely  with  the  adjoining  bones, 
so  that  it  is  frequently  lost  from  the  skeleton.  It  joins  the  os 
frontis  above,  the  os  maxillare  superius  before  and  below,  the 
os  planum  behind,  and  the  inferior  spongy  bone  in  the  nose. 


5.  Cheek  Bones,  (Ossa  Malarum,  Jugalia,  Os  de  la  Pommette.) 

These  bones,  two  in  number,  are  also  called  zygomatic  by 
many  anatomists*  They  are  situated  at  the  external  part  of  the 
orbit  of  the  eye,  and  form  the  middle  external  part  of  the  face. 

The  cheek  bone  is  quadrangular,  and  has  irregular  margins. 
It  consists  of  two  compact  tables  with  but  little  intermediate 
diploic  structure. 

There  are  three  surfaces  to  it..  That  which  contributes  to 
the  orbit  is  crescentic,  and  is  called  the  internal  orbitar  process. 
The  one  in  front  is  convex,  and  forms  part  of  the  face ;  and  be- 
hind the  latter  is  a  third  surface,  which  is  concave,  and  forms  a 
part  of  the  zygomatic  fossa.  Of  the  four  margins,  two  are  su- 
perior, and  two  inferior.  The  anterior  of  the  first  two  is  con- 
cave, and  rounded  off,  to  form  the  external  and  one-half  of  the 
lower  edge  of  the  orbit.  The  posterior  upper  border  above, 
is  thin  and  irregular,  and  to  it  is  attached  the  temporal  fascia:  it 
terminates  behind  by  a  short  serrated  margin,  for  articulating 
with  the  zygomatic  process  of  the  temporal  bone.  The  ante- 
rior inferior  margin,  is  serrated  its  whole  length,  for  articulating 
with  the  superior  maxillary  bone.  The  posterior  inferior  mar- 
gin gives  origin  to  part,  of  the  masseter  muscle.  Some  anato- 
mists admit,  also,  a  fifth  margin  to  this  bone,  which  is  towards 
the  bottom  of  the  orbit,  and  articulates  above  with  the  great 
wing  of  the  sphenoid  bone,  and  below  with  the  superior  maxil- 

*  Berlin,  Traite  D'Oatcol.  vol.  ii.  p.  143.     Paris,  1751. 


THE  FACE.  145 

lary.     Between  these  two  parts  is  a  notch,  forming  the  outer 
extremity  of  the  spheno-maxillary  slit. 

The  angles  of  this  bone  are  called  processes.  The  upper  one, 
which  is  continuous  with  the  external  angle  of  the  os  frontis,  is 
the  superior  orbitar,  or  angular  process.  The  orbitar  margin 
terminates  below,  in  the  inferior  orbitar,  or  angular  process. 
That  portion  of  the  bone  which  joins  with  the  zygoma  of  the  tem- 
poral, is  the  zygomatic  process;  and  the  fourth  angle  is  the  max- 
illary process. 

The  os  malae  articulates  with  four  bones ;  to  wit,  with  the 
maxillary,  frontal,  sphenoidal,  and  temporal. 

There  are  some  few  small  foramina  in  this  bone,  which  trans- 
mit nerves  and  blood  vessels. 


6.  Inferior  Spongy  Bones,  (Ossa  Spongiosa  ant  Ttirbinata  Infe- 
rior a,  Cornets  Inferieurs.) 

This  pair  of  bones  is  situated  at  the  inferior  lateral  parts  of 
the  nose,  just  below  the  opening  into  the  antrurn  Highmorianum. 
They  are  very  thin  and  porous,  and  their  substance  is  extreme- 
ly light  and  spongy. 

The  internal  face  of  the  spongy  bone  is  towards  the  septum 
of  the  nose,  and  presents  an  oblong  rough  convexity.  The  ex- 
ternal face  has  a  corresponding  concavity  towards  the  maxillary 
bone.  The  superior  margin  presents,  in  front,  an  upright  pro- 
cess, which  joins  with  the  anterior  inferior  angle  of  the  ungui- 
form  bone,  to  form  the  nasal  duct.  Just  behind  this,  the  margin 
of  the  bone  is  turned  over  towards  the  antrum,  forming  a  broad 
hook,  which  rests  upon  the  lower  margin  of  the  orifice  of  the 
antrum,  and  diminishes  its  size.  From  the  superior  margin,  also, 
one  or  two  processes  not  unfrequently  arise,  whereby  this  bone 
joins  the  ethmoid.  The  inferior  margin  is  somewhat  thicker 
than  the  superior. 

The  anterior  extremity  of  this  bone  rests  upon  the  ridge 
across  the  root  of  the  nasal  process  of  the  upper  maxillary.  The 
posterior  extremity  rests,  in  like  manner,  upon  the  ridge  across 
the  nasal  plate  of  the  palate  bone.* 

*  In  some  rare  cases  this  bone  adheres  to  the  ethmoid,  so  as  to  become  a  part 
of  it. 

VOL.  I.— 13 


146  SKELETON. 

The  Ploughshare,  (Vomer.) 

This  single  bone  is  placed  between  the  nostrils,  and  forms  a 
considerable  part  of  their  septum.  It  is  frequently  more  in- 
clined to  one  side  than  to  the  other.  It  is  formed  of  two  laminae, 
between  which  there  is  a  very  thin  diploic  structure. 

The  sides  of  the  vomer  are  smooth  and  parallel.  It  has  four 
margins.  The  superior  is  the  broadest,  and  has  a  furrow  in  it 
for  receiving  the  azygous  process  of  the  sphenoid  bone.  The 
anterior  margin  being  directed  obliquely  downwards  and  for- 
wards, its  front  half  joins  the  cartilaginous  septum  of  the  nose, 
and  the  posterior  half  receives,  in  a  narrow  groove,  the  nasal 
plate  of  the  ethmoid. 

The  posterior  margin  of  the  vomer  is  smooth  and  rounded, 
making  the  partition  of  the  nostrils  behind.  The  inferior  mar- 
gin articulates  with  the  spine  or  ridge  of  the  superior  maxillary 
and  palate  bones,  which  exist  at  their  internal  border. 


(Lower  Jaw,  Os  Maxillare  Inferius,  Maxittaire  Inferieur.) 

This  bone  forms  the  lower  boundary  of  the  face,  and  is  the 
only  one  in  the  head  capable  of  motion.  In  early  life,  its  two 
halves  are  separable,  being  joined  at  the  middle  line  only  by 
cartilage;  but,  in  the  course  of  two  or  three  years  after  birth, 
they  are  consolidated,  and  the  original  cartilage  disappears, 

It  consists  of  a  body  or  region  which  corresponds  with  the 
teeth,  and  two  extremities  or  branches. 

The  inferior  part  of  the  body  presents  a  thick  and  rounded 
edge,  which  is  the  base.  The  upper  part  of  the  body  is  formed 
by  the  alveolar  cavities  for  receiving  the  teeth.  The  line  of 
union  between  the  halves,  being  called  the  symphysis,  is  marked 
in  front  by  an  elevated  ridge,  terminated  below  by  the  ante- 
rior mental  tubercle  a  triangular  rising.  In  many  subjects 
this  tubercle  is  bounded  on  each  side  by  a  rounded  prominence 
of  bone,  which  gives  to  the  forepart  of  the  jaw  an  unusual 
squareness  in  the  living  subject.  Just  above  the  latter  promi- 
nence, there  is,  on  each  side,  a  transverse  depression,  from 
which  arises  the  levator  muscle  of  the  lower  lip.  On  a  line 
with  this  depression,  and  removed  a  little  distance  from  its  ex- 


THE  FACE.  147 

ternal  extremity,  under  the  interstice  between  the  second  small 
and  the  first  large  molar  tooth,  is  the  anterior  mental  or  maxil- 
lary foramen,  the  termination  of  a  large  canal  in  either  side  of 
the  bone,  and  which  conducts  the  inferior  maxillary  blood  ves- 
sels and  nerve  to  the  teeth.  The  foramen  is  directed  obliquely 
upwards  and  backwards,  and  transmits  the  remains  of  these 
blood  vessels  and  the  nerve  to  the  face.  The  chin  is  that  part 
of  the  bone  between  the  anterior  mental  foramina.  As  the  al- 
veolar processes  do  not  exist  in  early  life,  and  in  very  advanced 
age  when  the  teeth  are  lost,  the  anterior  mental  foramen  in 
such  cases  is  very  near  the  superior  margin  of  the  bone.  At 
it  an  obtuse  ridge  of  bone  commences,  and  which  ends  in  the 
root  or  anterior  edge  of  the  coronoid  process.  The  alveolar 
processes  of  the  last  three  molar  teeth  are  placed  within  this 
ridge,  and  project  over  the  internal  face  of  the  bone. 

The  internal  or  posterior  face  of  the  lower  jaw  is  also  marked 
at  the  symphysis  by  a  ridge  passing  from  the  superior  to  the  in- 
ferior margin.  At  the  lower  part  of  this  ridge  is  a  cleft  pro- 
cess, the  posterior  mental  tubercle.  Below  this  tubercle,  on  ei- 
ther side,  is  a  shallow  fossa,  for  receiving  the  digastric  muscle. 
Between  the  lower  margin  of  the  bone  and  the  protuberance 
occasioned  by  the  alveolar  processes  of  the  larger  molar  teeth, 
is  an  oblong  large  fossa,  made  by  the  pressure  of  the  sub-max- 
illary gland. 

The  alveolar  processes  form  a  semicircle,  the  extremities  of 
which  are  carried  backwards  with  a  slight  divergence.  The 
parietes  of  the  processes  are  thin,  and  present  cutting  edges. 
They  of  course  correspond, vin  number  and  shape,  with  the  roots 
of  the  teeth  which  they  have  to  accommodate.  The  anterior 
ones  are  longer  than  the  posterior.  As  a  general  rule,  the  alve- 
olar processes  may  be  said  to  come  and  depart  with  the  teeth*, 
but,  when  a  single  tooth  is  extracted,  the  alveolar  cavity  not 
unfrequently  is  filled  up  with  osseous  matter,  the  edge  of  it  alone 
being  removed.  This  occurs  more  frequently  in  the  lower  than 
in  the  upper  jaw. 

The  base  of  the  lower  jaw  does  not  present  many  marks 
worthy  of  attention.  It  should  be  observed,  that  its  anterior 
part  is  thicker  than  the  posterior;  and  that  sometimes,  just  be- 


148  SKELETON. 

fore  the  angle  of  the  bone,  we  see  a  concavity  of  this  edge,  but 
generally  it  is  straight,  or  nearly  so. 

The  extremities  or  rami  of  the  lower  jaw  are  quadrilateral, 
and  rise  up  much  above  the  level  of  the  body.  The  superior 
margin  presents  a  thin  concave  edge,  bounded  in  front  by  the 
coronoid,  and  behind  by  the  condyloid  process.  The  coronoid 
process  is  triangular,  and  receives  the  insertion  of  the  temporal 
muscle;  its  base  is  thick,  but  its  apex  is  a  thin  rounded  point. 
The  condyloid  process  is  a  transverse  cylindrical  ridge,  directed 
inwards,  with  a  slight  inclination  backwards,  its  middle  being 
somewhat  more  elevated  than  the  extremities.  It  springs  from 
the  ramus  by  a  narrow  neck.  There  is  a  concavity  at  the 
inner  fore  part  of  its  neck  for  the  insertion  of  the  pterygoideus 
externus,  and  a  convexity  behind. 

The  external  face  of  the  ramus  is  flat,  but  marked  by  the  in- 
sertion of  the  masseter  muscle.  The  internal  face,  at  its  lower 
part,  is  flat  and  rough,  for  the  insertion  of  the  pterygoideus  in- 
ternus.  At  the  upper  part  of  this  roughness  is  the  posterior 
mental  or  maxillary  foramen,  through  which  the  inferior  maxil- 
lary vessels  and  nerve  pass.  It  is  partially  concealed  by  a  spine 
of  bone,  into  which  a  ligament  from  the  os  temporis  is  inserted. 
Leading  from  this  foramen  is  a  small  superficial  groove,  made 
by  a  filament  of  the  inferior  maxillary  nerve. 

The  angle  of  the  inferior  maxillary  bone,  formed  by  the 
meeting  of  the'base  and  the  posterior  margin  of  the  ramus,  pre- 
sents diversities  well  worth  attention,  at  .different  epochs  of  life, 
and  in  different  individuals.  In  very  early  life,  and  in  very 
advanced,  when  the  alveoli  are  absorbed,  it  is  remarkably  ob- 
tuse. In  most  middle-aged  individuals  it  is  nearly  rectangular. 
Besides  which,  its  corner  is  sometimes  bent  outwards  and  some- 
times inwards,  increasing  or  diminishing  thereby  the  breadth 
of  the  face  at  its  lower  part. 

The  substance  of  this  bone,  externally,  is  hard  and  compact. 
Internally  there  is  a  cellular  structure,  through  the  centre  of 
which  runs  the  canal  for  the  nerves  and  blood  vessels.  From 
this  canal  smaller  ones  are  detached,  containing  the  vascular  and 
nervous  filaments  which  go  to  the  roots  of  the  teeth.  The  max- 
illare  inferius  articulates  with  the  temporal  bones,  by  means  of 
their  glenoid  cavities. 


'THE  SUTURES.  149 

Remarks. — The  maxillare  inferius  has  a  greater  influence  on  the 
form  of  the  face  than  any  other  bone  entering  into  its  composi- 
tion. Sometimes  it  is  much  smaller  in  proportion  in  certain  in- 
dividuals than  in  others.  Sometimes  its  sides,  being  widely  se- 
parated, cause  a  great  shortening  to  the  chin,  and  breadth  to  the 
lower  hind  part  of  the  face.  In  many  instances,  the  alveolar 
processes,  in  front,  incline  obliquely  over  the  outer  circumfe- 
rence of  the  bone,  and  thereby  give  to  the  chin  the  appearance 
of  receding  considerably.  In  others,  the  alveoli  incline  over 
the  inner  circumference,  which  causes  the  chin  to  project  unu- 
sually. 


CHAPTER  III. 


GENERAL  CONSIDERATIONS  ON  THE  HEAD. 

HAVING  described  the  individual  bones  of  the  head,  it  will 
now  be  proper  to  consider  it  as  a  whole. 


SECT.  I. — OF  THE  SUTURES. 

Except  in  advanced  age,  the  bones  of  the  cranium  and  of  the 
face  are  very  distinctly  marked  off  and  united  by  sutures. 

The  latter  are  formed  by  the  proximate  edges  of  the  bones, 
presenting  a  multitude  of  sharp  serrated  points,  and  of  deep 
narrow  pits,  by  which  they  are  brought  into  accurate  and  firm 
contact.  Here  and  there,  in  the  sutures  which  unite  the  flat 
bones  of  the  cranium,  we  find  not  only  sharp  points,  but  com- 
plete dove-tail  processes  of  the  one  bone  received  into  corre- 
sponding cavities  of  the  other.  The  denticulation  of  the  sutures 
is  much  more  common,  and  much  better  marked,  on  the  exter- 
nal than  on  the  internal  surface  of  the  cranium.  On  the  latter, 
the  union  of  the  bones  is,  in  several  instances,  by  a  joint  nearly 
straight;  in  which  case,  the  denticulation  is  almost  exclusively 
confined  to  the  external  table  and  to  the  diploic  structure. 

The  Coronal  Suture,  (Sutura  Coronalis,)  so  named  from  its 

13* 


150 


SKELETON. 


corresponding  in  situation  with  the  garlands  worn  by  the  an- 
cients, begins  at  the  sphenoid  bone,  about  an  inch  and  a  quarter 
behind  the  external  angular  process  of  the  os  frontis.  It  in- 
clines so  much  backwards  in  its  ascent,  that  when  we  stand 
erect,  with  the  head  in  its  easiest  position,  a  vertical  line, 
dropped  from  its  point  of  union  with  the  sagittal  suture,  would 
pass  through  the  centre  of  the  base  of  the  cranium,  and  would 
cut  another  line  drawn  from  one  meatus  auditorius  externus  to 
the  other.  It  unites  the  frontal  bone  to  the  two  parietal. 

The  Sagittal  Suture  (Sutura  Sagiltalis)  unites  the  upper  mar- 
gins of  the  two  parietal  bones,  and  is  immediately  over  the  divi- 
sion between  the  hemispheres  of  the  cerebrum.  It  has  been 
stated  in  the  account  of  the  os  frontis,  that  sometimes  it  is  con- 
tinued through  the  middle  of  this  bone  down  to  the  root  of  the 
nose. 

The  Lambdoidal  Suture  (Sutura  Lambdaformis)  is  named 
from  its  resemblance  to  the  Greek  letter  lambda,  and  consists 
of  two  long  legs  united  angularly.  It  begins  at  the  posterior 
termination  of  the  sagittal  suture,  and  continues  down  to  the 
base  of  the  cranium,  as  far  as  the  jugular  eminences  of  the  occi- 
pital bone.  Its  upper  half  unites  the  occipital  to  the  parietal 
bones,  and  the  lower  half  the  occipital  to  the  temporal  bones. 
The  latter  half  is  sometimes  called  the  Additamentum  Suturae 
Lambdoides, 

The  Squamous  Suture  (Sutura  Squamosa]  is  placed  on  the 
side  of  the  head,  and  unites  the  parietal  to  the  temporal  bone. 
The  convex  semicircular  edge  of  the  latter  overlaps  the  concave 
edge  of  the  former.  The  squamous  suture  is  converted  into  the 
common  serrated  one,  where  the  upper  edge  of  the  angle  of  the 
temporal  bone  joins  the  parietal.  This  portion  is  called  the  Ad- 
ditamentum Suturse  Squamosae. 

The  squamous  mode  of  suture  unites,  likewise,  the  great  wing 
of  the  sphenoidal  to  the  temporal  angle  of  the  parietal. 

In  the  upper  part  of  the  lambdoidal  suture,  particularly,  we 
find  in  many  skulls  one  or  more  small  bones,  connected  to  the 
parietal  and  occipital  hones  by  serrated  margins.  They  are 


THE  SUTURES.  151 

called  the  ossa  Wormiana  or  Triquetra.  They  vary  very  much 
in  their  magnitude,  being  in  different  subjects  from  a  line  to  one 
inch,  or  an  inch  and  a  half  in  diameter.  I  have  seen  them  of 
the  latter  size,  and  even  larger,  occupying  entirely  the  place  of 
the  superior  angle  of  the  os  occipitis.  Most  commonly,  but  not 
always,  when  one  of  these  bones  exists  on  one  side  of  the  body, 
a  corresponding  one  exists  on  the  other.  A  congeries  of  these 
bones,  united  successively,  is  sometimes  found  in  the  lambdoidal 
suture;  in  such  cases  they  are,  for  the  most  part,  small.  Com- 
monly these  bones  consist,  like  the  other  bones  of  the  cranium, 
of  two  tables  and  an  intermediate  diploe,  and  form  an  integral 
portion  of  the  thickness  of  the  cranium;  sometimes,  however, 
they  compose  only  the  external  table.  M.  Bertin  says,  that 
he  has  seen  them,  also,  composing  only  the  internal  table  of  the 
cranium. 

All  the  sutures  mentioned  besides  the  lambdoid,  may  exhibit, 
at  any  of  their  points,  the  ossa  Triquetra  or  Wormiana.  I  have 
seen  them  in  the  coronal,  the  sagittal,  and  the  squamous,  but  in 
such  cases  they  are  small.  The  lambdoid  unquestionably  has 
them  most  frequently.  M.  Bertin  has  seen  a  large  square  bone 
at  the  fore  part  of  the  sagittal  suture,  occupying  the  place,  and 
presenting  the  form,  of  what  was  once  the  anterior  fontanel:  he 
has  also  seen  triquetral  bones  in  the  articulations  of  the  bones  of 
the  face.* 

The  sutures  described  belong  exclusively  to  the  cranium,  but 
there  are  others  common  to  it  and  to  the  face~.  The  sphenoidal 
suture  surrounds  the  bone  from  which  its  name  comes;  the  eth- 
moidal  suture  surrounds  the  ethmoidal  bone;  the  zygomatic  su- 
ture unites  the  temporal  and  malar  bones;  the  transverse  suture 
runs  across  the  root  of  the  nose,  and  also  unites  the  malar  bones 
to  the  os  frontis.  The  other  articular  surfaces  of  the  face  de- 
rive their  names  from  the  bones  they  unite,  and  do  not  merit  a 
particular  attention  at  this  time,  as  enough  has  been  said  in  the 
description  of  the  bones  themselves. 

The  base  of  the  cranium  is  remarkably  different,  in  the  man- 
ner  of  its  articulations,  from  the  upper  part.  The  surface,  in 
the  first  place,  is  very  rugged,  and  much  diversified  by  its  con- 

*  Berlin,  loc.  cit. 


152  SKELETON. 

nexion  with  muscles  and  bones:  besides  which,  there  is  a  con- 
siderable number  of  large  foramina  and  fissures  in  it  for  the 
blood  vessels  and  nerves.  To  guard  against  the  weakness 
arising  from  the  latter  arrangement,  nature  has  given  a  very  in- 
creased thickness  to  the  base,  particularly  where  much  pressure 
from  the  weight  of  the  head  exists,  and  has  applied  unusually 
broad  surfaces  of  bone  to  each  other  to  secure  them  from  dis- 
placement by  concussion,  and  different  kinds  of  violence.  These 
arrangements  are  particularly  manifest  at  the  junction  of  the 
cuneiform  process  of  the  occipital  bone  with  the  body  of  the 
sphenoid,  which,  in  middle  age,  is  anchylosed; — at  the  lower 
part  of  the  lambdoidal  suture; — and  at  the  margins  of  the  pe- 
trous portions  of  the  temporal  bones  where  they  touch  the  con- 
tiguous bones.  Whence  it  results  that  the  several  fastenings  of 
the  base  of  the  cranium,  and  also  of  the  upper  maxilla,  are  so 
complete  and  strong,  that  they  are  most  generally  perfectly  ex- 
empt from  dislocation;  and  when  the  violence  offered  to  them 
is  sufficiently  great,  the  bones,  in  place  thereof,  are  fractured. 

The  use  of  the  sutures,  in  the  cranium  and  upper  maxilla,  is 
somewhat  problematical;  for  as  none  of  the  bones  move,  the 
head  might  have  been  equally  well  arranged  by  being  made  of 
a  single  piece.  In  proof  of  which  it  is  only  necessary  to  recol- 
lect, that  in  the  very  aged  there  is  frequently  not  a  bone  of  the 
cranium  and  upper  maxilla  to  be  found  in  an  insulated  state: 
they  are  all  fused  into  the  adjoining  bones,  by  the  obliteration 
of  their  sutures.  The  old  notion  that  sutures  existed  for  the 
purpose  of  arresting  the  course  of  fractures,  and  for  opening  in 
some  diseased  conditions  of  the  brain,  has  been  very  justly  ex- 
ploded. We  know  lhat  a  fracture  will  traverse  a  suture  readily, 
and  that  the  opening  of  the  sutures  from  hydrocephalus  is  an 
occurrence  only  of  very  early  infancy,  where  the  sutures  have 
not  arrived  at  the  serrated  and  dove-tail  arrangement,  by  which 
they  are  subsequently  secured.  It  is  much  more  probable  that 
the  true  reason  for  the  existence  of  sutures,  is  found  among  the 
laws  peculiar  to  the  growing  state;  and  which  most  commonly 
are  suspended  after  the  several  developments  have  been  accom- 
plished. Thus,  the  head,  in  consequence  of  being  separated  by 
sutures  into  many  pieces,  is  more  readily  wrought  from  its  form 
and  size  in  the  embryo  state,  to  the  form  and  size  required  by 


THE  SUTURES.  153 

adult  life.  This  necessity  of  subdivision  into  many  pieces,  does 
not  depend  so  much  on  the  size,  as  on  the  shape  of  the  head. 
For  we  find  the  largest  animal,  as  the  elephant,  having  no 
more  sutures  than  the  smallest,  as  the  mouse.  This  opinion  is 
also  sustained  by  what  we  see  in  other  bones.  Bones  of  a 
very  simple  shape,  as  those  of  the  tarsus  and  carpus,  consist 
from  the  very  beginning  of  but  one  piece.  But  where  the 
shape  of  a  bone  is  complicated,  we  find  it,  while  growing, 
submitted  to  the  same  law  as  the  head  at  large,  and  consisting 
of  many  pieces.  In  such  cases  these  pieces  are  united  by  a 
species  of  suture  corresponding  precisely  with  the  form  of  su- 
ture observed  between  some  of  the  bones  of  the  cranium;  as, 
for  example,  between  the  occipital  and  the  sphenoid.  Thus, 
the  os  femoris,  till  adult  age,  consists  of  five  pieces:  its  two  ar- 
ticular extremities,  its  body,  its  trochanter  major,  and  its  tro- 
chanter  minor.  The  cranium  itself,  before  birth,  and  for  some 
time  after,  has  several  of  its  individual  bones  consisting  each 
of  two  or  more  pieces,  which  favours  still  more  the  idea. 

Some  persons  think  that  the  sutures  of  the  adult  are  only  re- 
mains of  an  arrangement  intended  exclusively  for  the  benefit»of 
the  partarient  state,  by  maintaining  a  plasticity  of  the  head  of 
the  foetus,  which  admits  of  its  diameters  accommodating  them- 
selves to  the  diameters  of  the  pelvis  of  the  mother.  This  the- 
ory is  rather  too  exclusive,  though  it  may  be  admitted  that  the 
sutures  in  a  foetal  head  have  that  use,  and  are  in  some  cases  of 
parturition  a  most  fortunate  coincidence,  by  which  the  lives  of 
both  parties  are  saved.  But  it  should  be  observed  that  in  a 
great  number  of  cases,  the  head  of  the  foetus  never  changes  its 
form  in  passing  through  the  pelvis,  because  the  passage  is  quite 
large  enough  without  it;  and,  again,  if  the  sutures  were  intend- 
ed expressly  for  the  parturient  state,  we  ought  not  to  find  them 
in  birds,  and  in  such  animals  as  are  hatched,  because  the  ne- 
cessity for  them  there  does  not  exist.* 

Upon  the  whole  we  may  safely  conclude,  that  the  sutures  of 
the  cranium  and  face  are  simply  a  provision  for  the  growing 
state,  and  that,  like  all  other  provisions  for  this  state,  it  also 
ceases  at  its  appropriate  period,  and  sometimes  leaves  not  a  ves- 

*  A  gentleman  whose  anatomical  writings  have  some  vogue  in  this  country, 
has  cut  the  Gordian  knot,  by  telling  us  that  they  are  "  accidental  merely,  and  of 
little  use!!  "—Anat.  of  the  Human  Body,  by  John  Bell,  Surgeon,  Edinburgh. 


154  SKELETON. 

tige  of  its  existence.  Occasionally,  indeed,  we  find  the  latter 
to  have  occurred  in  one  or  more  sutures,  even  before  the  age 
of  puberty,  as  I  have  repeatedly  witnessed  of  the  sagittal,  the 
squamous,  and  the  lambdoidal  sutures. 

The  manner  in  which  the  sutures  are  formed  is  sufficiently 
interesting:  they  are  generally  said  to  be  made  by  the  radii  of 
ossification,  from  the  opposite  bones  meeting  and  passing  each 
other,  so  as  to  form  a  serrated  edge.  This  explanation  may 
account  partially  for  the  shape  of  the  edge  of  the  sutures,  but 
not  for  their  invariable  position;  inasmuch  as  we  always  find 
the  sutures  in  the  same  relative  situation,  and  having  the  same 
course.  If  they  depended  exclusively  on  so  mechanical  a  pro- 
cess, as  the  rays  of  one  bone  shooting  across  the  rays  of  ano- 
ther by  their  own  force,  we  ought  to  find,  occasionally,  the  sa- 
gittal suture  more  on  one  side  of  the  head  than  on  the  other, 
and  not  straight,  because  in  some  instances  ossification  is  a 
more  rapid  process  on  one  side  than  on  the  other.  Moreover, 
in  all  cases  where  bones  arise  from  different  points  of  ossifica- 
tion, and  meet,  the  serrated  edge  should  be  formed;  and  parti- 
cularly in  the  flat  bones.  Observation,  however,  proves  that 
the  os  occipitis,  which  is  formed  originally  from  four  points  of 
ossification,  and  therefore  has  as  many  bones  composing  it  in 
early  life,  does  not  present  these  bones  afterwards  united  by  the 
serrated  edge.  The  acromion  process  of  the  scapula,  though 
originally  distinct  from  the  spinous,  never  unites  to  it  by  suture, 
but  always  by  fusion.  The  mode  of  junction  in  the  three  bones 
of  the  sternum  is  always  by  fusion.  In  short,  the  observation 
holds  good  in  numerous  other  instances. 

Berlin  and  Bichat,  reject  fully  the  mechanical  doctrine  con- 
cerning the  sutures,  and  present  one  founded  upon  reason  and 
observation,  and  susceptible  of  confirmation  by  any  accurate 
observer.  The  dura  mater  and  the  pericranium,  before,  ossifica- 
tion commences,  form  one  membrane  consisting  of  two  laminas. 
Partitions  pass  from  one  of  these  laminae  to  the  other,  which 
mark  off  the  shape,  or  constitute  the  mould  of  the  bones  long 
before  they  are  perfected.  The  peculiar  shape  of  the  bony 
junction,  or,  in  other  words,  of  the  sutures  or  edges  of  the  bones 
in  adult  life,  depends,  therefore,  exclusively  upon  the  original 
shape  of  the  partitions.  When  the  latter  are  serrated,  the  points 


THE  SUTURES.  155 

of  ossification  will  fill  up  these  serrse;  but  when  they  are  oblique, 
the  squamous  suture  will  be  subsequently  formed. 

This  theory  also  accounts  for  modes  of  junction  intermediate 
to  the  squamous  and  serrated  suture ;  for  the  formation  of  the 
ossa  Triquetra  or  Wormiana ;  for  their  existence,  form,  size,  and 
number,  in  some  skulls,  and  their  total  absence  in  others.  The 
inference  will  also  be  obvious,  that  in  all  ossifications  from  dif- 
ferent nuclei,  a  suture  will  not  be  formed,  where  the  membra- 
nous partitions  do  not  exist ;  but  that  the  bones  will  unite  after 
the  manner  of  such  as  are  fractured.  We  shall  also  understand, 
that  when  these  partitions  are  weak  and  imperfect,  either  from 
their  congenital  condition,  or  from  advanced  age,  as  happens  in 
all  sutures,  but  with  some  differences  of  time,  the  bones  of  the 
opposite  sides  are  fused  together  completely. 

The  partitions  which  determine  the  places  of  the  sutures,  may 
be  demonstrated  in  a  young  adult  skull  by  removing  with  mu- 
riatic acid  the  calcareous  portion  of  the  bones,  so  as  to  leave 
only  the  animal  part.  On  opening  the  sutu/e  after  this  process, 
it  will  be  seen,  that  the  pericranium  sends  in  its  partition,  which 
is  met  by  the  partition  coming  from  the  dura  mater.  Or,  if 
either  of  these  membranes  be  peeled  off,  its  contribution  of  par- 
tition will  appear  very  plainly  projecting  from  its  surface,  in 
the  form  of  a  ridge. 

Owing  to  congenital  hydrocephalus,  the  sutures  of  the  vault 
of  the  cranium  have  been  known  to  remain  open  for  years  after 
birth,  from  the  continued  augmentation  of  the  volume  of  the 
brain.  In  such  cases  additional  bones  are  sometimes  formed, 
manifesting  a  strong  attempt,  on  the  part  of  nature,  to  cover  the 
brain  with  bone.  I  obtained,  some  years  ago,  a  specimen  of 
this  kind  belonging  to  a  foetus  of  nine  months,  whose  head  was 
as  large  as  it  is  commonly  in  adult  life,  and  in  whom  there  were 
two  ossa  parietalia  on  one  side.  Morgagni,*  whose  authority 
is  proverbial  in  morbid  anatomy,  states,  that  a  learned  colleague 
and  intimate  friend  of  his,  Bernardin  Rammazzani,  aged  seven- 
ty, had  the  sutures  open  at  that  period  of  life.  He  does  not  say 
at  what  time  this  condition  of  them  appeared.  I  think  it  more 
probable  that  they  had  never  been  closed,  though  Morgagni 

*  Causes  and  Seats  of  Disease,  Letter  3d,  Art.  8th. 


156  SKELETON. 

leaves  the  reader  to  infer,  that  it  was  a  circumstance  which  had 
arisen  from  a  violent  hemicrania,  with  which  the  patient  had 
been  seized  when  he  was  advanced  in  life.  Diemerbroek  found, 
in  a  woman  of  forty,  the  anterior  fontanel  not  ossified.  Bauhius' 
wife,  aged  twenty-six,  had  the  sutures  not  yet  closed.  Indeed, 
there  is  no  deficiency  of  well  authenticated  similar  instances, 
more  of  which  it  will  be  unnecessary  to  adduce.  It  may  be  ob- 
served here,  that  when  from  congenital  hydrocephalus,  attended 
with  much  extension  of  the  brain,  the  bones  of  the  cranium  are 
compelled  to  grow  beyond  their  usual  diameters,  they  are  un- 
commonly thin,  and  the  diploic  structure  is  very  imperfectly 
developed :  which  will  account  for  their  separation  at  any  period 
of  life,  from  the  fastening  being  so  slight. 


SECT.  II. OF  THE  DIPLOIC  STRUCTURE  OF  THE  CRANIUM. 

The  bones  of  the  cranium,  in  the  adult,  consist  of  an  external 
and  of  an  internal  table;  united  by  a  bony  reticulated  or  cellu- 
lar substance,  which  does  not  manifest  itself  very  distinctly  till 
two,  three,  or  even  more  years  are  passed,  by  the  infant.  The 
internal  table  of  the  skull  is  thinner  and  more  brittle  than  the 
external,  and  has  obtained,  from  that  cause,  the  name  of  vitreous 
table. 

The  cells  of  the  diploic  structure  are  not  to  be  confounded 
with  the  large  sinuses  that  exist  in  the  frontal,  the  temporal,  and 
the  sphenoidal  bones.  They  are  formed  under  different  circum- 
stances, and  do  not  communicate  with  them.  The  sinuses  are 
lined  by  a  mucous  membrane,  whereas  the  lining  membrane  of 
the  cells  of  the  diploe  corresponds  with  the  internal  periosteum 
of  other  bones.  I  have  a  preparation  now  before  me,  in  which 
the  diploic  structure  of  the  os  frontis  exists  between  its  sinuses 
and  the  external  table  of  the  bone:  in  the  same  head,  a  similar 
circumstance  existed  in  regard  to  the  temporal  bone;  from  which 
we  infer  that  the  diploic  structure,  in  these  places,  is  caused  to 
recede,  and  even  to  be  partially  obliterated,  when  the  develop- 
ment of  the  sinus  commences,  which  is  not  until  some  time  af- 
ter the  evolution  of  the  diploic  structure.  The  sphenoidal  bone, 
when  fully  evolved  in  its  body,  is  a  remarkable  instance  of  the 
recession  of  diploic  structure  for  the  purpose  of  forming  a  sinus. 


STRUCTURE  OF  THE  CRANIUM.  157 

In  the  diploe  of  the  dried  bones,  several  arborescent  channels* 
may  be  seen  by  the  removal  of  the  external  table.  They  were 
discovered  about  the  year  1805,  by  M.  Fleury,  while  he  was 
Prosecteur  at  the  School  of  Medicine  in  Paris:  and  engaged,  at 
the  instigation  of  the  venerable  Chaussier,  in  some  inquiries  re- 
lative to  the  structure  of  the  cranium.  The  account  given  by 
the  latter  is,  that  these  channels  are  occupied  in  the  recent  sub- 
ject, by  veins,  which,  like  all  others,  are  intended  to  return  the 
blood  to  the  heart.  These  veins  are  furnished  with  small 
valves,  have  extremely  thin  and  delicate  parietes,  and  commence 
by  capillary  ramifications,  coming  from  the  different  points  of 
the  vascular  membrane,  which  lines  the  cells  of  the  diploe. 
Their  roots  are  at  first  extremely  fine  and  numerous,  form  by 
their  frequent  anastomoses  a  kind  of  net-work,  and  produce  by 
their  successive  junction,  ramuscules,  branches,  and  large  trunks, 
which,  becoming  still  more  voluminous,  are  directed  towards 
the  base  of  the  cranium.  Some  variations  exist  in  regard  to  the 
number,  size,  and  disposition  of  these  trunks;  but  generally  one 
or  two  of  them  are  found  on  either  side  of  the  frontal  bone,  two 
in  the  parietal  bone,  and  one  on  either  side  of  the  occipital  bone. 
Anastomoses  exist  between  these  several  trunks>  by  which  the 
veins  In  the  parietal  bone  are  joined  to  those  in  the  frontal  and 
in  the  occipital.  Branches  from  the  right  side  of  the  head  also 
anastomose  with  some  from  the  left  side.  Besides  the  branches 
already  mentioned,  one  or  two  smaller  than  the  others  are  di- 
rected towards  the  top  of  the  head,  and  terminate  in  the  longi- 
tudinal sinus. 

The  descending  veins  of  the  diploe  communicate  in  their  pas- 
sage with  the  contiguous  superficial  veins,  and  empty  into  them 
the  blood  which  they  receive  from  the  several  points  of  the  di- 
ploe. These  communications  are  passed  through  small  fora- 
mina, which  penetrate  from  the  surface  of  the  bone  to  the  diploe. 
The  trunks  of  such  diploic  veins  as  are  continued  to  the  base  of 
the  cranium,  open  partly  into  the  sinuses  of  the  dura  mater,  and 
partly  into  the  venous  plexus  at  the  base  of  the  pterygoid  apo- 
physes  of  the  sphenoid  bone,  and  form  there  the  venous  commu- 
nications through  the  foramina  of  the  base  of  the  cranium,  called 

*  Chaussier,  Exposition  de  la  Structure  de  1'Encephale.     Paris,  1807. 

VOL.  I.— 14 


158  SKELETON. 

the  emissaries  of  Santorini.  Moreover,  there  are  communica-  , 
tions  sent  from  the  diploic  veins,  through  the  porosities  of  the 
internal  table  of  the  skull,  to  the  veins  of  the  dura  mater.  This 
fact  is  rendered  very  evident  by  tearing  off  the  skull-cap,  when 
the  surface  of  the  dura  mater  will  be  found  studded  with  dots  of 
blood,  and  the  internal  face  of  the  bone  also,  particularly  in  apo- 
plectic subjects.  It  appears,  indeed,  that  the  arteries  of  the 
cranium  are  principally  distributed  on  its  external  surface,  and 
the  veins  on  its  internal  surface  and  diplo£. 

In  the  infant,  the  diploic  veins  are  small,  straight,  and  have 
but  few  branches:  in  the  adult,  they  correspond  with  the  descrip- 
tion just  given,  and,  in  old  age,  they  are  still  more  considerable, 
forming  nodes  and  seeming  varicose.  In  children,  when  the  bones 
are  diseased,  they  partake  of  the  latter  character.  In  order  to 
see  them  fully,  the  external  table  of  the  skull  must  be  removed, 
both  from  its  vault  and  base,  with  a  chisel  and  mallet.  This 
operation  will  be  much  facilitated  by  soaking  the  head  pre- 
viously in  water  for  two  days. 

SECT.  IIT. THE  INTERNAL  SURFACE  OF  THE  CRANIUM. 

The  points  for  study  in  viewing  the  cranium  as  a  whole,  are 
generally  the  same  as  have  been  presented  in  the  detail  of  each 
bone.  It  is,  nevertheless,  useful  to  regard  the  structure  in  its 
connected  state,  as  new  views  are  thus  presented  of  the  rela- 
tive situation  of  parts,  and  of  the  formation  of  the  several  fossae 
and  cavities. 

The  cavity  for  containing  the  brain  is  regularly  concave 
above,  and  is  there  called  the  arch  or  vault;  but  below,  it  is  di- 
vided into  several  fossae,  and  is  called  the  base. 

The  whole  cavity  is  lined  by  the  dura  mater,  and,  in  the  adult, 
presents  round  superficial  depressions  made  by  the  convolutions 
of  the  brain.  These  depressions  are  seldom  deep  enough  to  pre- 
vent the  internal  periphery  of  the  vault  and  sides  of  the  crani- 
um, from  being  nearly  parallel  with  their  external  surface. 

On  the  Vault,  or  arch,  are  to  be  seen,  on  the  middle  line,  the 
frontal  spine,  extending  from  the  ethmoid  bone  halfway  or  more 
up  the  os  frontis:  also,  the  gutter  for  the  longitudinal  sinus  lead- 
ing from  this  spine  along  the  sagittal  suture,  and  terminating  at 


SURFACE  OF  THE  CRANIUM.  159 

the  internal  occipital  protuberance.  On  either  side  of  this  gut- 
ter are  the  arborescent  channels,  made  by  the  great  middle  ar- 
tery of  the  dura  mater.  In  this  section,  we  also  see  the  inter- 
nal face  of  the  os  fronlis,  excepting  its  orbitar  processes;  the 
parietal  bones;  and  the  superior  fossae  in  the  occipital  bone,  for 
the  posterior  lobes  of  the  cerebrum. 

The  Base  of  the  cranium  internally  presents  a  very  unequal 
surface,  abounding  in  deep  depressions,  processes,  and  foramina. 
On  its  middle  line,  extending  from  before  backwards,  the  follow- 
ing objects  should  be  remarked.  The  foramen  coscum  at  the 
front  of  the  crista  galli;  and,  at  either  side  of  the  latter,  the  eth- 
rnoidal  gutter,  perforated  with  holes.  These  gutters  are  bound- 
ed, laterally,  by  the  internal  margin  of  the  orbitar  processes  of 
the  os  frontis,  and  behind  by  the  sphenoid  bone.  At  the  fore 
part  of  the  gutter  is  the  oblong  foramen  for  transmitting  to  the 
nose  the  internal  nasal  nerve,  and  about  half  an  inch  behind  this 
foramen,  in  the  suture,  with  the  os  frontis,  is  the  inner  orifice 
of  the  foramen,  called  the  anterior  internal  orbitar,  which  leads 
the  same  nerve  from  the  orbit.  Immediately  behind  the  ethmoi- 
dal  fossae  the  sphenoid  bone  presents  a  plane  surface,  upon  which 
are  placed  the  olfactory  nerves  and  the  contiguous  part  of  the 
brain.  Behind  this  plane  is  the  fossa,  running  from  one  optic 
foramen  to  the  other,  for  lodging  the  optic  nerves.  Behind  this, 
again,  is  the  sella  turcica  or  pituitary  fossa,  bounded  at  its  two 
anterior  angles  by  the  anterior  clinoid  processes,  and  behind  by 
the  posterior  clinoid  process.  Posterior  to  the  latter  is  a  plane 
square  surface  of  the  sphenoid  bone,  continuous  with  the  inter- 
nal surface  of  the  cuneiform  process  of  the  os  occipitis.  On 
the  latter  is  the  depression  called  basilar  gutter,  for  receiving  the 
medulla  oblongata,  and  which  is  bounded  below  by  the  great 
occipital  foramen.  From  this  foramen  to  the  internal  occipital 
protuberance,  proceeds  the  inferior  limb  of  the  occipital  cross. 

On  both  sides  of  the  ethmoidal  bone  is  a  convex  surface ;  called, 
however,  the  anterior  fossae  of  the  base  of  the  cranium,  and 
formed  by  the  orbitar  processes  of  the  os  frontis  and  the  little 
wings  of  the  sphenoid  bone,  for  lodging  the  anterior  lobes  of  the 
brain.  This  surface  is  terminated  behind  by  the  rounded  edge 
of  the  little  wings,  which  is  received  into  the  fissure  between  the 


160  SKELETON. 

anterior  and  middle  lobes  of  the  brain.   Just  anterior  to  this  edge 
is  the  fronto-sphenoidal  suture. 

On  the  sides  of  the  sella  turcica  are  the  middle  fossae  of  the 
base  of  the  cranium.  They  are  very  wide  externally,  where 
they  are  bounded  by  the  squamous  portions  of  the  temporal  bones, 
but  narrow  internally,  where  they  are  bounded  by  the  Sella 
Turcica.  The  little  wings  of  the  sphenoidal  bone  terminate 
them  in  front,  and  form  there  a  crescentic  edge  hanging  over 
their  cavity.  Their  posterior  margin  is  the  superior  ridge  of 
the  petrous  bone.  This  bone  is  placed  very  obliquely,  inwards 
and  forwards,  and  its  point  almost  reaches  the  posterior  clinoid 
process.  At  the  anterior  part  of  the  fossa  is  the  sphenoidal 
fissure  or  foramen,  of  the  sphenoidal  bone.  Just  above  the 
base  of  this  fissure  is  the  foramen  opticum,  partially  concealed 
by  the  anterior  clinoid  process.  Just  below  the  base  of  the  fis- 
sure is  the  foramen  rotundum.  At  the  point  of  the  petrous 
bone,  by  the  side  of  the  posterior  clinoid  process,  is  the  in- 
ternal orifice  of  the  carotid  canal.  On  a  line  with  the  latter, 
exteriorly,  is  the  foramen  ovale.  Two  lines  behind  the  latter 
is  the  foramen  spinale.  The  groove  formed  by  the  middle  arte- 
ry of  the  dura  mater,  may  be  traced  from  the  foramen  spinale 
along  the  anterior  margin  of  the  squamous  bone.  Near  the 
upper  part  of  this  bone  the  groove  bifurcates;  the  larger  chan- 
nel runs  upwards  into  a  groove  on  the  tip  of  the  great  sphe- 
noidal wing,  into  the  principal  groove  of  the  parietal  bone, 
which  commences  at  the  temporal  angle  of  the  latter.  The 
smaller  groove  runs  horizontally  backwards,  and  just  above 
the  base  of  the  petrous  bone  is  continued  also  into  the  parietal 
bone.  On  the  front  of  the  petrous  portion  may  be  seen  the 
hiatus  Fallopii.  The  sphenoidal  suture  runs  through  these  fossae, 
in  the  examination  of  which,  the  reception  of  the  spinous  pro- 
cess of  the  sphenoid  bone,  between  the  squamous  and  petrous 
portions  of  the  temporal,  will  be  readily  understood. 

On  each  side  of  the  foramen  magnum  occipitis  are  the  two  pos- 
terior fossas  of  the  base  of  the  cranium,  formed  by  the  posterior 
faces  of  the  petrous  bones,  the  angles  of  the  mastoid  portions  of 
the  temporal  bones  and  by  that  surface  of  the  occipital  bone  be- 
low its  horizontal  ridges.  These  two  fossae  are  very  partially  se- 


SURFACE  OF  THE  HEAD.  161 

parated  by  the  inferior  ridge  of  the  occipital  cross.  The  lambdoi- 
dal  suture  traverses  these  fossae.  At  the  junction  between  the 
petrous  bone  and  the  basilar  process  of  the  occipital,  in  the  course 
of  the  suture,  is  a  groove  for  the  inferior  petrous  sinus.  The 
groove  conducts  to  the  posterior  foramen  lacerum,  which  has  a 
small  part  separated  from  it  by  the  little  spine  of  the  petrous  bone, 
which,  with  the  assistance  of  the  dura  mater,"  forms  a  distinct 
foramen  for  the  eighth  pair  of  nerves.  The  posterior  foramen 
lacerum  beingcommon  to  the  temporal  and  occipital  bones,  is  oc- 
casionally much  larger  on  the  right  than  on  the  left  side:  in 
which  case,  the  groove  that  leads  from  it  along  the  angle  of  the 
temporal  bone,  the  inferior  corner  of  the  parietal,  and  the  hori- 
zontal limb  of  the  occipital  cross,  is  also  larger.  Above  the  fo- 
ramen lacerum  are  the  meatus  auditorius  internus  and  the  inter- 
nal orifice  of  the  aqueduct  of  the  vestibule.  Between  the  foramen 
lacerum  and  foramen  magnmn  occipitis  is  the  anterior  condyloid 
foramen.  The  two  posterior  fossae  of  the  base  of  the  cranium 
contain  the  cerebellum. 


SKCT.  IV.  —  OF  THE  EXTERNAL  SURFACE  OF  THE  HEADi 

Anatomists,  of  modern  times,  consider  the  external  surface 
of  the  head  as  forming  or  representing  three  ovals  and  two 
triangles  each  of  which  constitutes  a  region.  The  first  oval  is 
the  whole  superior  convex  part  of  the  cranium ;  or,  in  other 
words,  the  external  surface  of  its  vault.  The  second  oval  is 
formed  by  the  inferior  surface  of  the  cranium,  and  of  the  face. 
The  third  oval -is  formed  by  the  lower  front  part  of  the  os  fron- 
tis,  and  by  the  face.  Each  side  of  the  head  forms  one  of  the 
triangular  regions. 

The  superior  region  is  so  simple,  and  its  parts  have  been  so 
closely  sketched,  that  it  is  unnecessary  to  repeat  the  descrip- 
tion. 

The  inferior  region  or  oval,  extends  from  the  chin  to  the  oc- 
cipital protuberance,  and  is  bounded  in  its  transverse  diameter 
by  the  superior  semicircular  ridges  of  the  os  occipitis,  by  the 
mastoid  processes,  and  by  the  rami  and  base  of  the  lower  jaw. 
This  surface  is  subdivided  into  Palatine,  Guttural,  and  Occipital 
sections  or  regions. 

The  Palatine  region  or  section,  is  formed  by  the  superior 

14* 


162  SKELETON. 

maxillary  and  palate  bones,  above,  and  by  the  inferior  maxil- 
lary bone,  laterally  and  below.  It  is  a  deep  fossa,  the  circum- 
ference of  which  is  represented  by  the  letter  U,  the  open  part 
being  behind.  The  whole  upper  surface  of  the  palatine  region, 
presents  a  number  of  small  rough  elevations  and  fossa?,  for  the 
attachment  of  the  lining  membrane  of  the  mouth.  The  surface 
is  divided  into  two  equal  parts  by  the  long  or  middle  palate  su- 
ture, which  is  crossed  at  its  posterior  part  by  the  transverse 
palate  suture.  The  posterior  margin  of  the  hard  palate  is  con- 
cave on  each  side  of  the  mouth;  and  from  it  is  suspended  the 
soft  palate.  The  point  in  the  centre  of  this  margin  gives  ori- 
gin to  the  azygos  uvula?  muscle. 

The  foramina  on  this  surface,  are  the  anterior  palatine  or 
foramen  incisivum,  in  the  long  palate  suture  just  behind  the  in- 
cisor teeth,  and  on  either  side,  behind,  between  the  palate  and 
pterygoid  process  of  the  palate  bone,,  bounded  exteriorly  by  the 
upper  maxillary,  is  .the  posterior  palatine  foramen.  About  one 
or  two  lines  behind  this,  is  another  foramen,  in  the  base  of  the 
pterygoid  process  of  the  palate  bone,  through  which  pass  fibril- 
la?,  of  the  same  nerve  that  occupies  the  posterior  palatine  fora- 
men. The  posterior  palatine  foramen  also  transmits  an  artery 
to  the  soft  palate,  the  mark  of  whose  course  may  be  seen  at  the 
base  of  the  alveolar  processes  for  the  molar  teeth. 

The  depth  of  the  palatine  fossa  depends  on  the  state  of  the 
teeth.  When  they  are  removed  by  old  age,  and  the  alveolar 
processes  also,  what  wras  palatine  fossa  is  almost  a  plane  sur- 
face; and  in  many  instances  of  extreme  old  age,  entirely  so, 
excepting  the  part  formed  by  what  remains  of  the  lower  jaw. 
The  separation  from  the  nose  is,  also  extremely  thin,  and  not 
unfrequently  imperfect.  The  transverse  diameter  of  the  mouth 
is  much  decreased,  in  consequence  of  the  absorption  of  the  al- 
veolar processes  taking  place,  from  the  outside  towards  the  in- 
side. 

The  internal  surface  of  the  lower  jaw  has  been  sufficiently 
described  in  the  account  of  that  bone. 

The  Guttural,  Region  of  the  base  of  the  head  is  formed  by  the 
cuneiform  process  of  the  os.occipitis,  in  the  centre;  by  the  infe-. 
rior  face  of  the  petrous  bones,  laterally  and  behind;  by  the  body 
and  great  wing  of  the  sphenoid  bone,  laterally  and  in  front; 
nnd  by  the  several  bones  contributing  to  the  orifice  of  the  pos- 
terior narcs. 


SURFACE  OF  THE  HEAD.  163 

It  is  bounded  anteriorly  by  the  pterygoid  fossae  and  openings 
of  the  nose,  and  behind  by  the  mastoid  and  condyloid  processes. 
It  consists,  consequently,  in  one  part,  which  is  horizontal,  and  in 
another,  which  is  vertical.  In  regard  to  the  horizontal  portion, 
its  inequalities,  processes,  and  fossae,  have  been  already  stated. 
The  relative  position  of  its  foramina,  cannot,  however,  be  studied 
except  in  the  united  bone.  The  following  rules  will  afford 
some  assistance  in  determining  their  position,  even  on  the  liv- 
ing body. 

A  line  passing  from  the  anterior  margin  of  one  mastoid  pro- 
cess to  the  corresponding  point  of  the  other,  will  subtend  the 
stylo-mastoid  foramina,  and  the  posterior  margin  of  the  foramina 
lac-era;  it  will  also  touch  the  base  of  the  styloid  processes,  and 
cut  into  halves  the  condyl.es  of  the  occiput.  A  line,  three-eighths 
of  an  inch  in  advance  of  this,  run  through  the  middle  of  the 
meatus  auditorius  externus,  will  indicate  the  posterior  margins 
of  theglenoid  cavities,*  and  cut  in  half  the  inferior  end  of  the  ca- 
rotid orifices  or  foramina,  and  touch  the  anterior  margins  of  the 
anterior  condyloid  foramina.  Another  line,  one  fourth  of  an  inch 
in  advance  of  the  latter,  will  cut  through  the  centre  of  the  gle- 
noid  cavity,  and  subtend  the  styloid  process  of  the  sphenoid 
bone,  and  the  bony  orifice  of  the  Eustachian  tube  in  the  tempo- 
ral bone.  A  line  passing  between  the  external  ends  of  the  tuber- 
cles of  the  temporal  bones,  will  subtend  the  foramina  ovalia  and 
the  foramina  lacera  anteriora.  The  foramen  spinale  is  about 
equi-distant  from  the  last  two  lines. 

The  foramen  lacerum  anterius,  being  at  the  point  of  the  pe- 
trous bone,  is  occasioned  by  the  latter  not  filling  up  the  space 
between  it  and  the  sphenoidal  and  occipital  bones.  The  de- 
ficiency is  supplied,  in  the  recent  state,  by  cartilage.  Precisely 
opposite  to  the  point  of  the  petrous  bone,  is  the  posterior  orifice 
of  the  foramen  pterygoideum,  from  which  emerges  the  pterygoid 
nerve,  and  penetrating  this  cartilage  immediately  divides  into 
two  branches:  one  going  to  the  carotid  canal,  and  being  one  of 
the  roots  of  the  Sympathetic  nerve;  and  the  other,  ascending 
into  the  cranium,  becomes  the  Vidian  nerve  or  superficial  pe- 
trous. 

The  vertical  portion  of  the  Guttural  Region  presents  the  pos- 

*  By  glenoid  cavity  is  here  meant  the  whole  of  the  depression  in  the  temporal 
bone,  and  not  merely  the  surface  for  the  contlyle  of  the  lower  jaw. 


164  SKELETON. 

terior  orifices  of  the  nostrils,  separated  from  each  other  by  the 
vomer.  On  each  side  are  the  pterygoid  processes  of  the  sphe- 
noid bone,  and  above  is  its  body.  The  pterygoid  fossa,  formed 
between  the  external  and  internal  process,  and  the  long  unci- 
form  termination  of  the  latter  with  the  broader  and  shorter  ter- 
mination of  the  former,  will  also  be  observed. 

The  Occipital  region  of  the  base  of  the  head,  placed  imme- 
diately behind  the  other,  may  be  considered  to  include  the  mas- 
toid  processes,  and  the  foramen  magnum  occipitis,  and  to  be 
bounded  behind  by  the  tuber  of  the  occiput  and  its  superior 
transverse  ridges.  Its  marks  have  been  sufficiently  dwelt  upon, 
in  the  description  of  the  os  occipitis. 

The  third  oval  will  be  described  in  detail  in  a  short  time. 

On  the  side  of  the  head,  where  we  consider  the  triangular 
region  to  exist,  the  arch  formed  by  the  malar  bone  and  the  zy- 
gomatic  process  of  the  temporal,  forms  a  very  conspicuous 
feature.  The  anterior  abutment  of  this  arch  is  formed  by  the 
greater  part  of  the  malar  bone,  and  a  considerable  portion  of 
the  malar  process  of  the  superior  maxillary.  The  posterior 
abutment  is  formed  by  the  root  of  the  zygomatic  process  of  the 
temporal  bone.  Its  superior  margin  is  thin,  for  the  insertion 
of  the  temporal  aponeurosis :  the  inferior  margin  is  thick,  and 
is  divided,  by  a  projection  in  its  middle,  into  an  anterior  and  a 
posterior  surface,  marking  the  origins  of  the  two  portions  of  the 
masseter  muscle.  There  is  a  very  considerable  vacancy  be- 
tween the  zygoma  and  the  side  of  the  head,  occupied  by  the 
coronoid  process  of  the  lower  jaw,  the  temporal  and  the  exter- 
nal pterygoid  muscles.  The  coronoid  process  is  just  within 
the  zygomatic  arch,  and  the  tip  rises  three  or  four  lines  above 
its  inferior  margin. 

The  large  depression  within  the  zygoma  is  the  temporal  fossa. 
All  that  portion  of  the  side  of  the  head  beneath  the  ridge  lead- 
ing from  the  external  angular  process  of  the  os  frontis,  and  run- 
ning along  the  surface  of  the  parietal  bone,  is  tributary  to  the 
temporal  fossa.  The  bones,  therefore,  which  form  it,  are  the 
frontal,  the  parietal,  the  temporal,  the  great  wing  and  the  ex- 
ternal pterygoid  process  of  the  sphenoid  bone,  and  the  posterior 
face  of  the  superior  maxillary  and  malar  bones.  The  arrange- 


NASAL  CAVITIES.  165 

ment  of  the  squamous  suture  is  well  seen  in  this  fossa,  also  the 
junction  of  the  pterygoid  bone  with  the  parietal  and  frontal,  by 
the  overlapping  of  the  great  wing  of  the  former.  At  the  inferior 
part  of  the  latter,  is  the  pointed  process,  from  which  one  head 
of  the  external  pterygoid  muscle  arises. 

At  the  bottom  of  the  temporal  fossa  there  is  a  narrow  slit 
partitioned  from  the  nose  by  the  nasal  plate  of  the  palate  bone. 
This  slit,  from  its  position,  is  called  the  Pterygo-maxillary  fossa. 
It  is  triangular,  the  base  being  upwards  and  the  point  down- 
wards. The  base  reaches  to  the  bottom  of  the  orbit.  From 
the  base  there  leads  into  the  nose  the  spheno-palatine  foramen 
for  transmitting  the  lateral  nasal  nerve  and  blood  vessels.  Ex- 
ternally to  this  foramen,  and  somewhat  above  it,  is  the  foramen 
rotundum  for  the  upper  maxillary  nerve.  On  a  level  with  the 
spheno-palatine  foramen,  and  running  horizontally  through  the 
base  of  the  pterygoid  process,  is  the  pterygoid  foramen  for  the 
nerve  of  the  same  name.  Running  vertically  downwards  from 
the  point  of  the  pterygo-maxillary  fossa,  is  the  posterior  pala- 
tine canal  for  transmitting  the  nerve  and  artery  of  the  same 
name.  The  upper  part  or  base  of  the  pterygo-maxillary  fossa, 
is  continuous  with  a  large  fissure  in  the  bottom  of  the  orbit 
called  the  spheno-maxillary. 


SECT.  V. OF  THE  NASAL  CAVITIES. 

The  nose  consists  of  two  large  cavities  or  fossae,  in  the  mid- 
dle of  the  bones  of  the  upper  jaw,  and  has  a  very  irregular  sur- 
face. Its  cavities  are  separated  from  one  another  by  a  vertical 
septum,  consisting  in  the  vomer  and  in  the  nasal  lamella  of  the 
ethmoid  bone.  This  septum  presents  a  surface  which  is  per- 
fectly prlane,  with  the  exception,  that  in  some  subjects  it  is 
slightly  convex  on  one  side,  and  concave  on  the  other.  It  is 
deficient  in  front. 

The  upper  part  of  either  nostril  is  formed  by  the  cribriform 
plate  of  the  ethmoid  bone ;  in  front  of  this  the  surface  is  very 
oblique,  being  made  by  the  os  nasi;  posteriorly  there  is  a  ver- 
tical gutter  on  the  body  of  the  sphenoid  bone,  in  the  middle  of 
which  is  the  orifice  of  the  sphenoidal  cell.  The  distance  be- 
tween the  cellular  part  of  the  ethmoid  and  the  septum  nasi  is 


106  SKELETON. 

not  more  than  three  lines.  The  double  row  of  foramina  in  the 
cribriform  plate  is  very  well  seen,  also  the  foramen  at  its  ante- 
rior part  for  transmitting  the  nasal  branch  of  the  ophthalmic 
nerve;  the  groove  formed  by  the  latter  on  the  posterior  face  of 
the  os  nasi  is  also  very  distinct. 

The  bottom  of  either  nostril,  called  its  floor,  is  formed  by  the 
palate  process  of  the  superior  maxillary  and  palate  bones;  it  is 
somewhat  concave,  and  about  half  an  inch  wide;  its  width,  how- 
ever, is  not  uniform,  as  it  is  sometimes  wider  or  narrower  in 
front  than  it  is  in  the  middle.  In  it  is  seen  the  upper  orifice  of 
the  foramen  incisivum  at  the  anterior  point  of  the  vomer. 

The  external  or  orbitar  surface  of  the  nasal  cavity  is  very  ir- 
regular, presenting  a  number  of  projections  and  fossoe3  over 
which  the  Schneiderian  membrane  is  displayed.  It  is  formed 
by  the  upper  maxillary,  the  ethmoid,  the  unguiform,  the  palate, 
the  nasal,  the  lower  spongy,  and  the  sphenoid  bones.  In  the 
middle  of  the  posterior  part  of  the  ethmoid  is  the  upper  meatus 
of  the  nose,  a  deep  fossa,  bounded  above  by  the  cornet  of  Mor- 
gagni,  and  receiving  the  contents  of  the  posterior  ethmoidal 
cells,  by  one  or  more  orifices.  At  the  posterior  termination  of 
this  fossa  is  the  spheno-palatine  foramen.  The  middle  spongy 
bone  forms  the  lower  boundary  of  the  ethmoid ;  between  it  and 
the  lower  spongy  or  turbinated  bone,  is  the  middle  meatus  of 
the  nose,  a  fossa  of  considerable  size,  but  of  unequal  surface. 
At  the  fore  part  of  the  middle  meatus  is  a  vertical  projection, 
formed  by  the  ductus  ad  nasum  and  lachrymal  fossa.  Just 
behind  this  ridge,  is  an  interval  between  it  and  the  anterior 
part  of  the  ethmoid,  through  which  the  os  uriguis  may  be  seen. 
When  the  middle  spongy  bone  is  broken  off,  immediately  be- 
neath its  anterior  part  a  channel  obliquely  vertical,  is  seen  in 
the  ethmoid,  which  leads  to  the  frontal  sinus,  through  the  an- 
terior ethmoidal  cell.  This  cell,  from  its  peculiar  shape  and 
function,  is  called  infundibulum.  Behind  this  oblique  channel 
is  another  oblique  channel,  parallel,  but  smaller;  in  which  seve- 
ral orifices  may  be  found  of  the  anterior  ethmoidal  cells.  The 
anterior  channel  has,  indeed,  for  the  ethmoidal  cells  other  ori- 
fices besides  the  infundibulum,  which  are  smaller,  and  below 
the  latter.  It  is  bounded,  in  front,  by  a  sharp,  thin  ridge  of  the 
ethmoid,  the  lower  extremity  of  which  contributes  to  close  the 
large  opening  into  the  sinus  maxillare. 


ORBITS  OF  THE  EYES.  .  167 

Commonly  about  the  middle  of  the  middle  meatus  of  the  nose, 
but  varying  very  much  in  different  subjects,  is  the  orifice  of  the 
sinus  maxillare,  or  antrum  Highmorianum.  Its  precise  situa- 
tion and  direction  are  so  very  uncertain,  that  its  orifice  is  found 
with  some  difficulty  in  the  fresh  state,  in  great  numbers  of  per- 
sons. Not  unfrequently  I  have  seen  this  orifice  high  up,  under 
the  anterior  extremity  of  the  middle  spongy  bone. 

The  inferior  meatus  of  the  nose  is  bounded  above  by  the 
lower  spongy  bone,  and  below  by  the  palate  processes.     It  ex- 
tends the  whole  length  of  the  nostril.     At  the  anterior  part  of4 
this  meatus  above,  is  the  orifice  of  the  ductus  ad  nasum,  which 
communicates  with  the  orbit  of  the  eye. 

The  nostril  presents  an  increased  width,  anterior  to  the  points, 
where  the  spongy  bones  cease:  this  space  is  bounded  on  the 
orbitar  side  by  the  nasal  bone,  and  the  nasal  process  of  the 
upper  maxillary.  There  is  an  increase  of  transverse  diameter 
also  at  the  posterior  part  of  the  nostril,  behind  the  points  where 
the  spongy  or  turbinated  bones  cease.  This  space  is  bounded 
externally  by  the  nasal  plate  of  the  palate  bone,  and  by  the  in- 
ternal pterygoid  process. 

The  posterior  nares,  or  orifices  of  the  nostrils,  are  oval,  and 
are  completely  separated  by  the  posterior  margin  of  the  vomer. 
In  the  dried  skeleton,  on  the  contrary,  the  anterior  nares  have 
a  common  orifice,  from  the  deficiency  of  the  bony  septum  be- 
tween them. 


SECT.  VI. ORBITS  OF  THE  EYES. 

The  orbits  of  the  eyes  are  the  conoidal  cavities  in  the  face, 
presenting  their  bases  outwards  and  forwards,  and  their  apices 
backwards;  so  that  the  diameter  of  either  orbit,  if  continued, 
would  decussate  that  of  its  fellow  in  the  pituitary  fossa  or  sella 
turcica.  Seven  bones  form  the  orbit,  the  os  frontis,  the  os 
malse,  the  os  maxillare  superius,  the  os  planum,  the  os  un- 
guis,  the  os  sphenoides,  and  the  os  palati.  Its  cavity  is  some- 
what quadrangular,  besides  being  conoidal.  The  angles  are 
particularly  well  marked,  in  most  subjects,  at  its  base  or  ori- 
fice; which  resembles  an  oblong,  having  its  long  diameter  in 
some  persons  placed  almost  horizontally,  and  in  others  oblique- 


168  SKELETON. 

ly  downwards  and  outwards.  Immediately  within  the  orifice 
the  cavity  is  enlarged,  owing  to  the  projection  of  the  orbitary 
ridge  of  the  os  frontis,  and  the  elevation  of  the  anterior  inferior 
margin  of  the  orbit,  so  that  the  greatest  diameter  is  there  ra- 
ther vertical  than  horizontal.  From  this  point  the  orbit  de- 
creases gradually  in  size  to  the  sphenoidal  fissure,  or  the  supe- 
rior foramen  lacerum  of  the  orbit  which  forms  its  apex.  The 
internal  walls  of  the  two  orbits  are  nearly  parallel,  in  conse- 
quence of  the  cuboidal  figure  of  the  os  ethmoides,  which  is 
placed  between  them. 

The  superior  face  or  roof  of  the  orbit  is  triangular  and  con- 
cave :  it  is  very  thin,  and  presents  but  a  slight  septum  between 
the  eye  and  the  brain.  Almost  the  whole  of  it  is  formed  by  the 
orbitar  process  of  the  os  frontis,  its  point  only  being  made  by 
the  little  sphenoidal  wing.  The  depression  for  the  lachrymal 
gland,  at  its  external  anterior  part,  is  very  perceptible.  The 
trochlea  for  the  superior  oblique  muscle  of  the  eye,  is  also  well 
seen  about  three-quarters  of  an  inch  above  the  point  of  the  in- 
ternal angular  process  of  the  os  frontis.  Just  at  the  outer  side 
of  this  depression  is  the  foramen  or  notch  for  the  frontal  artery 
and  nerve.  The  optic  foramen  may  be  seen,  very  readily,  pass- 
ing through  the  little  wing  of  the  sphenoid  bone. 

The  inferior  face,  or  the  floor  of  the  orbit,  is  also  triangular 
and  concave,  and  is  formed  by  the  orbitar  process  of  the  upper 
maxillary  bone  principally;  being  assisted,  however,  at  its  an- 
terior external  margin,  by  a  portion  of  the  malar  bone;  and,  at 
its  point  behind,  by  the  orbitar  process  of  the  palate  bone.  The 
latter  cannot  be  seen  very  distinctly  in  the  articulated  bones, 
owing  to  its  great  depth  in  the  orbit;  but,  when  the  external 
side  of  the  orbit  is  removed  with  a  saw,  its  position  is  placed  in 
an  interesting  light.  The  floor  of  the  orbit  is  thinner  than  its 
roof,  and  forms  a  very  slight  separation  from  the  maxillary  sinus. 
It  is  terminated  behind  by  the  spheno-maxillary  fissure,  or  in- 
ferior foramen  lacerum  of  the  orbit;  a  large  slit,  which,  com- 
mencing at  the  base  of  the  sphenoidal  fissure,  separates  the  great 
wing  of  the  sphenoidal  bone  from  the  ethmoidal,  the  palate,  and 
the  upper  maxillary  bones.  This  fissure  runs  obliquely  out- 
wards, so  as  to  have  its  external  extremity  terminated  by  the 
malar  bone.  Near  the  external  extremity  is  seen  the  com* 


THE  FACE.  169 

mencement  of  the  infra-orbitar  canal,  for  transmitting  the  su- 
perior maxillary  nerve  and  artery. 

The  external  face  of  the  orbit  is  also  triangular,  and  very  ob- 
lique. It  is  formed  by  the  malar  bone,  and  by  the  orbitar  face 
of  the  great  sphenoidal  wing.  It  is  defined  below  by  the  spheno- 
maxillary  fissure,  and  above  by  the  suture  which  unites  the 
frontal  to  the  malar,  and  to  the  great  wing  of  the  sphenoidal 
bone.  It  is  terminated,  at  the  apex  of  the  orbit,  by  the  sphe- 
noidal fissure. 

The  internal  face  of  the  orbit  is  an  oblong  square,  nearly 
parallel,  as  mentioned,  with  the  corresponding  face  of  the  other 
orbit.  It  is  formed  principally  by  the  orbitar  face  of  the  eth- 
moid, called  the  os  planum,  but  at  the  apex  of  the  orbit  a  small 
portion  of  the  body  of  the  sphenoid  bone  contributes  to  it,  and 
anteriorly  is  the  os  unguis.  It  is  bounded  behind  by  the  sphe- 
noidal fissure,  in  front  by  the  lachrymal  ridge  on  the  nasal  pro- 
cess of  the  os  maxillare  superius,  and  above  and  below  by  the 
upper  and  lower  ethmoidal  sutures.  In  the  upper  of  these  su- 
tures there  are  generally  two,  sometimes  three,  foramina,  the 
anterior  of  which  transmits  an  artery,  a  vein,  and  a  nerve,  to 
the  nose ;  the  posterior  transmits,  also,  an  artery  and  a  vein  to 
the  same. 

The  lachrymal  fossa  is  well  worthy  of  attention:  it  is  seen  to 
commence  small  at  the  upper  part  of  the  os  unguis,  and  to  in- 
crease in  size  till  it  is  formed  into  a  complete  canal,  the  ductus 
ad  nasum,  leading  to  the  nose,  by  the  upper  maxillary  and  the 
inferior  spongy  bones.  The  direction  of  the  canal  is  almost  ver- 
tically downwards,  inclining  very  slightly  backwards.  It  was 
stated,  that  the  fossa  in  the  fore  part  of  the  os  unguis  is  some- 
times supplanted  by  the  increased  breadth  of  the  nasal  process,  a 
fact  of  some  importance  to  an  operator  for  fistula  lachrymalis. 

SECT.   VII. OF  THE  FACE,  TOGETHER  WITH    SOME    REMARKS   ON  THE 

FACIAL  ANGLE,  AND  ON   NATIONAL  PECULIARITIES. 

The  anterior  oval  of  the  head  extends  from  the  frontal  pro- 
tuberances to  the  base  of  the  lower  jaw,  and  from  the  malar 
bone  of  one  side  to  the  malar  of  the  other  inclusively.  This 
oval  is  divided  into  two  symmetrical  or  equal  halves,  by  the 

VOL.  I.— 15 


170  SKELETON. 

vertical  suture,  which  unites  the  bones  of  the  opposite  sides  of 
the  face. 

In  the  infant,  the  frontal  protuberances  are  always  well 
marked,  from  their  being  the  centres  of  ossification  for  the  two 
halves  of  the  os  frontis ;  in  the  adult,  they  are  frequently  not 
raised  above  the  common  level  of  the  bone.  The  superciliary 
protuberances  just  above  the  internal  half  of  the  orbitary  or  su- 
perciliary ridges,  are  generally  somewhat  prominent,  but  they 
vary  very  much  in  this  respect  in  different  individuals.  Between 
these  ridges  the  frontal  bone  is  sometimes  raised  into  a  vertical 
elevation,  continuous  with  the  dorsum  of  the  nose,  as  is  more 
frequently  seen  in  young  persons. 

The  nose,  or  pyramidal  convexity,  formed  by  the  nasal  pro- 
cesses of  the  superior  maxillary,  and  by  the  nasal  bones,  is  con- 
cave above,  and  extremely  prominent  below.  The  prominence 
of  it  depends  upon  the  development  of  the  ossa  nasi.  I  have 
frequently  seen  the  latter  curtailed  to  about  one-half,  and  even 
one-third  of  their  usual  breadth,  and  also  diminished  in  length; 
which  is  followed  by  an  unusual  flatness  of  the  nose  :  the  pecu- 
liarity had  been  presented  to  me  till  lately  only  in  negroes;  but, 
since  then,  I  have  also  met  with  it  in  the  skulls  of  white  sub- 
jects: it  is.,  however,  much  more  uncommon  in  the  latter.  The 
anterior  orifice  of  the  nose  is  cordiform,  the  base  being  below: 
the  centre  of  the  base  is  marked  by  a  rough  point,  called  the 
anterior  nasal  spine. 

The  cheek  bones  form,  on  either  side  of  the  face,  a  conside- 
rable prominence,  depending  much  upon  the  length  of  the  ma- 
lar process  of  the  upper  maxillary  bones.  In  savage  tribes,  this 
prominence  is  frequently  a  characteristic  trait,  and  may  depend 
upon  the  greater  development  of  the  upper  maxillary  sinuses, 
probably  from  the  more  frequent  or  more  intense  employment 
of  the  organ  of  smelling.  The  elevation  of  the  cheek  bone  is 
always  conspicuous  in  emaciated  subjects,  from  the  fat  around 
its  base  being  absorbed. 

The  alveolar  processes  with  the  teeth  produce,  in  certain  sub- 
jects, a  very  conspicuous  projection  in  the  face ;  varying,  how- 
ever, considerably  in  different  individuals,  and  in  different  tribes 
of  human  beings.  There  is  but  little  doubt  of  the  organization 
of  some  men  being  more  coarse  and  animal  than  that  of  others, 


THE  FACE.  171 

even  in  members  of  the  same  family.  The  circumstance  occa- 
sionally manifests  itself  by  unusually  large  and  long  teeth,  and 
by  alveolar  processes  of  corresponding  dimensions.  Savage 
nations  have  almost  invariably  this  peculiarity,  which  is  kept 
up  among  them,  not  only  by  hereditary  influence  from  father 
to  son,  but  also  by  the  actual  habits  of  the  individual  being  pro- 
ductive of,  and  favourable  to  this  arrangement.  It  would  be 
interesting  to  know  whether  from  their  articles  of  food  general- 
ly being  harder  to  masticate  than  such  as  are  used  by  civilized 
people,  they  do  not  contribute  to,  or  even  produce  a  greater  de- 
velopment in  the  organs  of  mastication.  Analogy  is  in  favour 
of  the  opinion,  because  the  arms  or  the  legs  ar6  always  developed 
in  proportion  to  the  vigour  and  frequency  of  the  exercise  to 
which  they  are  put.  Ploughmen  have  large  legs.  Blacksmiths 
have  large  arms.  Persons  whose  habits  of  exercise  do  not  call 
into  action  any  part  of  the  body,  to  the  exclusion  of  other  parts, 
have  finer  and  more  graceful  forms  than  labourers.  It  is  there- 
fore, probable,  that  the  ease  and  gracefulness  of  movement,  said 
to  mark  the  polished  and  accomplished  man  of  fashion,  depend 
upon  the  harmonious  action  of  his  whole  frame,  derived  from 
this  proportionate  development  of  all  its  parts.  Besides  the  in- 
fluence of  exercise  upon  the  organs  of  mastication,  the  passions 
or  faculties  of  the  mind  not  unfrequently  manifest  themselves 
there.  Individuals  of  unusual  ferocity  and  savageness,  have 
frequently  large  teeth  and  alveolar  processes.  The  gnashing 
of  the  teeth  has,  in  all  ages,  been  considered  one  of  the  most 
striking  signs  of  anger. 

While  speaking  of  these  indications  of  man  in  a  savage  and 
uncultivated  state,  it  will  be  understood  that  I  allude  to  such 
tribes  as  are  engaged  in  the  chase,  and  in  other  active  modes  of 
subsistence,  and  whose  habits  are  not  settled  down  into  the  agri- 
cultural or  pastoral  condition.  It  is  quite  possible  for  one  in  the 
latter  situation  to  be  equally  uninstructed,  on  every  point  of 
mental  improvement,  and  to  be  much  inferior  in  capacity,  to  one 
of  the  former ;  yet  his  articles  of  food,  and  the  sensations  and 
passions  in  which  he  indulges,  will  give  no  very  prominent  out- 
line to  his  face,  but  only  mark  it  by  the  general  expression  of 
dulness  and  ignorance. 

The  outline  of  the  face  is  marked  also  by  depressions  or  fossae. 


172  SKELETON. 

Those  for  the  eyes  and  for  the  nose  have  been  studied,  and  ar- 
rest at  once  the  attention  of  the  most  superficial  inquirer.  Im- 
mediately below  the  orbits  are  the  canine  fossa3  formed  in  the 
centre  of  the  front  of  the  upper  maxillas.  Just  above  the  incisor 
teeth  of  these  bones  are  the  superior  incisive  fossae.  Below  the 
inferior  incisor  teeth,  on  each  side,  also,  is  the  inferior  incisive 
fossa. 

In  most  adults  the  face  projects  somewhat  beyond  the  crani- 
um, but  there  is  a  considerable  diversity  in  this  respect  between 
different  tribes  of  human  beings.  Camper,*  who  has  paid  much 
attention  to  this  arrangement,  has  designated  it  under  the  term 
of  the  facial  angle,  which  he  marks  off  by  two  straight  lines. 
One  is  drawn  from  the  lower  front  part  of  the  frontal  bone  to 
the  point  called  the  anterior  nasal  spine  at  the  orifice  of  the 
nose,  and  between  the  ends  of  the  roots  of  the  incisor  teeth  of 
the  upper  jaw;  the  other,  from  this  latter  point  to  the  middle  of 
the  rneatus  auditorius  externus,  or  thereabouts.  The  facial 
angle  is.  included  between  these  two  lines.  In  Caucasian,  or 
European  heads,  this  angle  is  about  eighty  degrees.  In  the 
negro,  or  Ethiopian,  it  is  about  seventy  degrees;  and  in  the 
Mongolian  or  copper-coloured  man,  about  seventy-five  de- 
grees. 

An  invariable  relation  is  established  between  the  extent  of 
the  facial  angle,  the  capaciousness  of  the  cranium,  and  the  size 
of  the  nasal  and  palatine  cavities.  The  nearer  the  approach  is 
to  a  rectangle,  the  smaller  is  the  cavity  of  the  nose,  and  qf  the 
mouth,  and  the  greater  is  that  of  the  cranium,  thereby  mani- 
festing a  more  voluminous  and  intellectual  brain.  On  the  con- 
trary, the  more  acute  that  the  facial  angle  is,  the  smaller  is  the 
volume  of  brain,  and  the  larger  are  the  nose  and  mouth.  This 
is  so  frequently  the  case,  that  Bichat  considers  it  almost  a  rule 
in  our  organization,  that  the  development  of  the  organs  of  taste 
and  smell,  is  in  an  inverse  ratio  to  that  of  the  brain,  and  con- 
sequently to  the  degree  of  intelligence.  \ 

This,  like  other  general  rules,  is  subject  to  exceptions,  in  con- 
sequence of  the  facial  angle  varying  in  its  size,  from  causes 
which  have  no  connexion  with  the  degree  of  development  of 
the  brain.  Thus  an  unusual  prominence  and  thickness  in  the 

*  Dissertation  sur  les  Differences  du  Visage  chez  les  Hommes.    Utrecht,  179L 


THE  FACE.  173 

lower  part  of  the  os  frontis,  from  an  increased  capaciousness 
of  the  sinuses,  will  make  the  facial  angle  appear  less  acute. 
The  absorption  of  the  alveolar  processes,  after  the  loss  of  the 
teeth,  will  produce  the  same  result  in  our  measurements  of  the 
facial  angle.  The  heads  of  infants,  previously  to  the  appear- 
ance and  full  growth  of  the  teeth,  have  always  the  facial  angle 
less  acute  than  the  heads  of  adults:  in  some  cases  an  angle  of 
ninety  degrees  is  presented  in  them.  On  the  contrary,  a  growth 
of  teeth,  and  consequently  of  the  alveolar  processes,  dispropor- 
tionate to  the  size  of  the  body  of  the  upper  jaw,  will  cause  the 
facial  angle  to  project  very  considerably  even  in  an  individual 
of  the  Caucasian  race.  Similar  objections  may  be  brought 
against  the  indications  of  the  inferior  line.  The  fair  state  of 
this  argument  appears  then  to  be,  that  the  doctrine  of  the  facial 
angle,  though  correct  in  a  majority  of  instances,  has  numerous 
exceptions  from  individual  peculiarities,  and  that  there  is  no 
race  of  human  beings  which  does  not  present  the  facial  angle 
in  all  its  ranges  from  seventy  to  ninety  degrees, 

With  the  view  to  meet  such  objections  and  establish  a  rule 
of  more  uniformity,  M.  Cuvier  has  proposed  to  ascertain  re- 
sults from  a  vertical  section,  by  which  it  appears  that  the  Cau- 
casian cranium  is  four  times  the  area  of  the  face;  whereas  in 
the  negro  the  face  is  a  fifth  larger  in  proportion. 

In  regard  to  the  various  configurations  of  the  human  face 
and  stature,  depending  upon  habits  and  circumstances  conti- 
nued through  a  long  succession  of  ages  and  generations,  the 
following  views  of  one,*  pre-eminently  qualified  to  judge,  will 
not  be  uninstructive. 

"•  Although  there  appears  to  be  but  one  human  species,  since 
all  its  individuals  can  couple  promiscuously,  so  as  to  produce  a 
prolific  offspring,  we  yet  remark  in  it  certain  hereditary  con- 
formations, which  constitute  what  arc  called  races.  Of  them 
there  are  three  which  are  eminently  distinct  in  appearance: 
they  are,  the  white  or  Caucasian;  the  yellow  or  Mongolian; 
the  negro  or  Ethiopian. 

*  Rcgne  Animal,  par  M.  Ic  Chcv.  Cuvier,  torn,  1,  p,  94.     Pari^  1817, 


174  SKELETON. 

"  The  Caucasian  race,  to  which  we  belong,  is  distinguished 
by  the  beautiful  oval  form  of  the  head ;  and  it  is  this  which  has 
given  birth  to  the  most  civilized  nations,  and  to  those  which 
have  generally  ruled  over  the  others.  It  has  some  differences 
in  the  shade  of  the  complexion,  and  in  the  colour  of  the  hair. 

"  The  Mongolian  is  known  by  its  prominent  cheek  bones, 
flat  face,  narrow  and  oblique  eyes,  straight  and  black  hair,  thin 
beard,  and  olive  complexion.  It  has  formed  vast  empires  in 
China  and  Japan,  and  has  sometimes  extended  its  conquests  on 
this  side  of  the  Great  Desert ;  but  its  civilization  has  always 
remained  stationary. 

The  Negro  race  is  confined  to  the  south  of  Mount  Atlas;  its 
complexion  is  black,  its  hair  woolly,  its  skull  compressed,  nose 
flattish ;  its  prominent  mouth  and  thick  lips  make  it  manifestly 
approach  the  monkey  tribe ;  the  people  which  compose  this 
race  have  always  remained  in  a  state  of  barbarism. 

"  The  race  from  which  we  are  descended  is  called  Caucasian, 
because  tradition  and  also  the  lineage  of  nations,  would  appear 
to  trace  it  to  the  group  of  mountains  situated  between  the  Cas- 
pian and  the  Black  seas,  (on  the  borders  of  Europe,)  from  whence 
it  has  radiated  in  every  direction.  The  people  of  Caucasus,  as 
also  the  Georgians  and  Circassians,  are  considered,  even  at 
the  present  day,  the  handsomest  in  the  world.  The  principal 
branches  of  this  race  are  distinguishable  by  the  analogies  .of 
language.  The  Armenian  or  Syrian  division,  directed  its  course 
towards  the  south,,  and  has  given  birth  to  the  Assyrians,  the 
Chaldeans,  and  the  untameable  Arabs,  who,  after  Mahomet, 
(werd  very  near  becoming  masters  of  the  world;  to  the  Pheni- 
cians,  the  Jews,  and  the  Abyssinians,  which  were  Arabian  colo- 
nies; and  it  is  very  probable  that  the  Egyptians  also  are  de- 
scended from  the  same  source.  It  is  from  this  branch,  (the 
Syrian,)  always  inclined  to  mysticism,  that  the  most  widely 
extended  religions  have  sprung.  Science  and  literature  have 
flourished  among  them  occasionally,  but  always  under  fantas- 
tic forms,  and  with  a  figurative  style. 

"  The  Indian,  German,  and  Pelasgic  branch,  is  infinitely  more 
extended,  and  was  divided  at  a  much  earlier  period ;  we,  never- 


THE  FACE.  175 

theless,  recognise  the  greatest  resemblance  between  its  four 
principal  languages;  which  are,  the  Sanscrit,  at  present  the 
sacred  language  of  the  Hindoos,  and  mother  of  all  the  dialects 
of  Hindostan ;  the  ancient  language  of  the  Pelasgi,  which  is  the 
common  mother  of  the  Greek,  the  Latin,  of  many  tongues 
which  are  now  extinct,  and  of  almost  every  language  spoken 
in  the  south  of  Europe ;  the  Gothic  or  Teutonic,  from  which 
are  derived  the  languages  of  the  North  and  North  West,  such 
as  the  German,  Dutch,  English,  Danish,  Swedish,  and  their  dia- 
lects ;  and  lastly,  the  language  called  Sclavonian,  from  which 
come  those  of  the  north-east,  as  the  Russian,  Polish,  Bohe- 
mian, &c. 

"  It  is  this  great  and  respectable  branch  of  the  Caucasian 
race,  which  has  carried  farthest  Philosophy,  the  Arts  and  Sci- 
ences, and  which  has  been  for  ages  the  depository  of  them. 

"  This  branch  was  preceded  in  Europe  by  the  Celts,  who 
came  from  the  north,  and  were  formerly  very  much  extended, 
but  are  now  confined  to  the  most  western  parts;  and  by  the 
Cantabrians,  who  passed  from  Africa  into  Spain,  and  are,  at 
present,  almost  confounded  with  the  numerous  nations  whose 
posterity  has  been  blended  in  this  peninsula. 

"  The  ancient  Persians  have  the  same  origin  with  the  Indian 
branch;  and  their  descendants,  even  at  the  present  day,  bear 
the  strongest  marks  of  affinity  to  the  European  nations. 

"  The  Scythian  or  Tartarian  branch,  first  directing  their 
course  to  the  north  and  north-east,  always  led  erratic  lives  in 
the  vast  plains  of  those  countries:  and  they  have  only  left  them 
to  return  and  destroy  the  more  comfortable  establishments 
of  their  brethren.  The  Scythians,  who,  at  so  remote  a  period 
of  antiquity,  made  irruptions  into  Upper  Asia;  the  Parthians, 
who  destroyed  there  the  power  of  the  Greeks  and  Romans;  the 
Turks,  who  overthrew  there  that  of  the  Arabs,  and  subjugated 
in  Europe  the  unhappy  remnant  of  the  Greek  nation,  were 
swarms  of  this  stock;  the  Philanders  and  the  Hungarians  are 
colonies  of  it,  in  some  measure  astray  among  the  Sclavonian 
and  Teutonic  nations.  The  north  and  east  of  the  Caspian  Sea, 
their  original  country,  are  still  inhabited  by  people  of  the  same 
origin,  and  speaking  similar  languages;  but  they  are  there  in- 
termixed with  an  infinity  of  other  petty  nations,  of  different 
origins  and  languages.  The  Tartar  nation  has  always  re- 


176  SKELETON. 

mained  more  unmixed  in  all  that  tract  of  country,  extending 
from  the  mouth  of  the  Danube,  to  beyond  the  Irtisch,  from 
which  they  so  long  threatened  Russia,  and  where  they  have  at 
last  been  subdued  by  her.  The  Mongolians,  however,  in  their 
conquests  have  blended  their  blood  with  these  people,  and  many 
traces  of  this  intermixture  are  discovered,  principally  among 
the  Western  Tartars." 

"  The  Mongolian  race  commences  to  the  east  of  this  Tartar 
branch  of  the  Caucasian,  and  prevails  thence  to  the  Eastern 
Ocean.  Its  branches,  the  Calmucks  and  Halkas,  still  nomadic 
or  unsettled,  occupy  the  Great  Desert.  Thence  have  their  an- 
cestors, under  Attila,  under  Genghis,  and  under  Tamerlane, 
spread  far  and  wide  the  terror  of  their  name.  The  Chinese 
come  from  this  race,  and  are  not  only  the  most  anciently 
civilized  of  it,  but,  indeed,  of  any  nation  yet  known.  A  third 
branch,  (the  Montchoux)  has  recently  conquered  China,  and 
continues  to  govern  it.  The  Japanese  and  Coreans,  and  al- 
most all  the  hordes  which  extend  to  the  north-east  of  Siberia, 
under  the  domination  of  Russia,  belong  also  to  it  in  a  great 
measure.  If  we  except  a  few  Chinese  literati,  the  whole  Mon- 
golian race  is  universally  addicted  to  the  different  sects  of  the 
worship  of  Fo. 

"  The  origin  of  this  great  race  appears  to  have  been  in  the 
Altay  Mountains,*  as  ours  was  in  the  Caucasian;  but  it  is  impos- 
sible to  follow  so  well  the  clue  of  its  different  branches.  The 
history  of  these  wandering  people,  is  as  fugitive  as  their  establish- 
ments; and  the  records  of  the  Chinese,  from  being  confined  to 
their  own  empire,  afford  us  but  short  and  vague  accounts  of  their 
neighbouring  nations.  The  affinities  of  their  languages  are  also 
but  too  little  known  to  guide  through  this  labyrinth. 

te  The  languages  of  the  north  of  the  peninsula  beyond  the 
Ganges,  and  also  that  of  Thibet,  bear  some  affinity  to  the  Chinese, 
at  least,  in  their  monosyllabic  nature,  and  the  people  who  speak 
them  are  not  without  traits  of  resemblance  to  the  other  Mongo- 
lian nations;  but  the  south  of  this  peninsula  is  inhabited  by  the 
Malays,  a  much  handsomer  people,  whose  race  and  language  arc 
spread  over  the  coasts  of  all  the  islands  of  the  Indian  Archipe- 

*  A  range  in  the  north  of  Asia,  about  5000  miles  long.. 


FCETAL  HEAD.  177 

lago,  and  have  occupied  almost  all  those  of  the  Southern  Ocean. 
On  the  largest  of  the  former,  especially  in  the  uncultivated  and 
savage  parts,  we  find  other  men,  who  have  woolly  hair,  black 
complexion,  and  negro  visage,  and  who  are  all  extremely  bar- 
barous. The  most  known  are  the  Papuas,  a  name  by  which 
they  may  be  generally  denominated. 

"  It  is  not  easy  to  refer  either  the  Malays  or  Papuas,  to  any 
one  of  the  three  great  races;  but  can  the  former  be  plainly  dis- 
tinguished from  their  neighbours,  the  Caucasian  Hindoos  on  one 
side,  and  the  Mongolian  Chinese  on  the  other?  We  must  con- 
fess that  we  do  not  find  them  to  possess  sufficient  characteris- 
tics to  enable  us  to  answer  this  question.  Are  the  Papuas  ne- 
groes, who  formerly  straggled  along  the  Indian  Ocean?  We 
have  neither  drawings  nor  descriptions  sufficiently  clear  to  re- 
ply to  this  question. 

"  The  inhabitants  of  the  north  of  the  two  continents,  the 
Samoiedes,  the  Laplander^,  and  the  Esquimaux,  sprung,  ac- 
cording to  some  authorities,  from  the  Mongolian  race.  Agree- 
ably to  others,  they  are  but  a  degenerate  offspring  of  the  Scy- 
thian and  Tartarian  branches  of  the  Caucasian  race. 

"  It  is  impossible  to  refer,  satisfactorily,  the  Americans  them- 
selves to  either  of  our  races  of  the  old  continent;  and  yet  they 
have  not  characteristics  precise  and  constant  enough  to  con- 
stitute a  distinct  race.  Their  copper-coloured  complexion  is 
not  sufficient;  their  hair,  which  is  generally  black,  and  their 
scanty  beard,  would  lead  us  to  refer  them  to  the  Mongolians, 
did  not  their  well  marked  features,  and  their  moderately  pro- 
minent noses,  oppose  such  an  arrangement;  their  languages 
are  as  innumerable  as  their  tribes,  and  we  have  yet  been  un- 
able to  discover  either  any  analogies  among  them,  or  with 
those  of  the  ancient  world."* 


SECT.  VIII. OF  THE  DEVELOPMENT  OF  THE  FCETAL  HEAD. 

The  foetal  head,  in  the  very  early  stages  of  gestation,  forms 
an  oval  vesicle,  constituting  the  greater  part  of  the  bulk  of  the 

*  On  this  subject,  see  also  Lectures  on  the  Physiology,  Zoology,  and  Natural 
History  of  Man,  by  W.  Lawrence.    London,  1822. 

Dictionnaire  des  Sciences  Med.  tome  XXI.     Paris,  1817. 
Histoire  Naturelle  de  L'Homme,  par  Lacapede.     Paris,  1821. 
Blumenbach  de  Variet.  Gen.  Hum.  Nat.  1794— abo  Decades,  1790—1814. 


178  SKELETON. 

embryo,  and  at  this  period  has  the  face  scarcely  visible.  The 
parietes  of  this  vesicle  are  formed  by  a  thin  membrane,  con- 
sisting of  two  layers,  the  external  of  which  is  the  pericranium, 
and  the  internal  layer  is  the  dura  mater.  These  layers  adhere 
so  closely  that  they  cannot  be  accurately  separated  by  the 
knife. 

About  the  third  month  of  the  embryo,  or  even  earlier,  ossifi- 
cation may  be  seen  at  several  points  of  the  cranium,  but  more 
extensively  about  its  base.  These  points  are  the  centres  of  os- 
sification, which  progressively  increase  towards  their  respec- 
tive circumferences,  by  the  deposite  of  new  bony  matter. 
Generally  the  base  of  the  cranium  begins  to  ossify  before  the 
vault,  and  is  entirely  ossified  at  birth,  with  the  exception  of  a 
few  parts,  as  the  clinoid  processes  and  the  ethmoid  bone. 

The  following  nuclei  of  ossification  show  themselves  between 
the  laminae  of  the  foetal  cranium,  from  the  third  to  the  fourth 
month.  One  at  the  anterior  part,  for  the  centre  of  either  side 
of  the  os  frontis;  one  for  the  centre  of  each  parietal  bone,  on 
the  upper  side  of  the  head;  one  on  the  side  of  the  head  below, 
for  the  squamous  portion  of  the  temporal  bone;  and  there  are 
several  for  the  occipital  bone.  These  points  extend  themselves 
in  radii;  and,  as  the  intervals  between  the  latter  become  wider 
by  their  divergence,  new  radii,  as  observed  elsewhere,  are  de- 
posited between  them.  In  some  of  the  bones,  the  radii,  from 
opposite  points,  in  the  progress  of  ossification  before  and  after 
birth,  meet  and  coalesce :  this  occurs  in  the  os  frontis  and  in 
the  os  occipitis. 

At  birth  the  contiguous  margins  of  the  flat  bones  simply  ap- 
proach each  other,  but  have  not  interlocked.  These  bones  con- 
sist then  of  but  one  table,  the  edges  of  which  are  very  finely  ser- 
ratedj  and  thereby  show  the  radii  of  ossification.  The  edges  are 
held  together  by  the  dura  mater,  internally,  and  the  pericranium, 
externally;  but  the  fissure  between  them  is  very  obvious,  and  so 
large  that  it  allows  very  readily  considerable  motion  and  the 
mounting  of  one  bone  upon  the  other  by  slight  pressure.  It  is 
always  to  be  observed  that  the  base  of  the  cranium  is  an  ex- 
ception to  the  latter  rule,  both  from  the  breadth  of  its  articulating 
surfaces,  and  from  its  comparatively  advanced  ossification.  In 
parturition,  therefore,  the  vault  of  the  cranium,  by  its  mobility, 
is  adjusted  to  the  contoar  of  the  pelvis,  but  the  base  does  not 


FCETAL  HEAD.  179 

yield  in  either  of  its  diameters  to  the  expulsive  powers  of  the  ute- 
rus. The  latter  provision,  however  inconvenient  in  parturition, 
is  of  the  greatest  consequence  immediately  afterwards;  for  with- 
out this  immobility  in  the  base  of  the  cranium,  whenever  the 
weight  of  the  head  was  thrown  upon  it,  the  pressure  of  the  ver- 
tebral column  would  drive  it  upwards,  to  the  injury  of  the  brain 
and  of  the  nerves  proceeding  from  it.  This  resistance,  it  may 
be  added,  is  still  farther  assisted  by  the  arched  figure  of  the  base 
of  the  cranium.  On  this  subject,  it  is  not  a  little  remarkable, 
that  even  the  heads  of  hydrocephalic  foetuses  have  the  bones 
of  the  base  fully  ossified,  and  in  contact,  so  as  to  support  the 
weight  of  the  head  in  the  vertical  position. 

Fontanels. — In  consequence  of  the  flat  bones  of  the  cranium 
ossifying  always  towards  the  circumference,  their  angles,  as  ob- 
served, being  the  longest  radii  from  their  centres,  are  the  last  in 
ossifying.  These  angles  are  commonly  incomplete  at  birth,  and 
the  membranous  spaces  which  represent  them  are  the  Fontanels. 
Of  these  there  are  six,  two  on  the  middle  line  of  the  head,  above, 
and  two  on  either  side.  The  former  afford  highly  important 
indications  to  the  midwife. 

The  anterior  fontanel  is  the  largest  of  all.  It  is  at  the  fore 
part  of  the  sagittal  suture,  and  is  produced  by  a  deficiency  in 
the  angles  of  the  parietal  bones,  and  of  the  contiguous  angles  of 
the  os  frontis.  It  is  quadrangular  or  lozenge-shaped;  and  the 
anterior  angle  is  generally  longer  than  the  others.  This  is  re- 
markably the  case,  when  the  sagittal  suture  is  continued  down 
to  the  root  of  the  nose.  The  posterior  fontanel  is  at  the  other 
extremity  of  the  sagittal  suture,  and  as  there  are  only  three 
points  of  bone  defective  there,  two  for  the  parietal  bones,  and 
one  for  the  occipital,  this  suture  is  triangular.  In  many  chil- 
dren, at  birth,  it  is  so  far  filled  up  as  to  be  scarcely  visible;  the 
three  membranous  sutures,  however,  which  run  into  it,  make 
its  position  sufficiently  discernible  by  the  finger. 

Of  the  two  fontanels,  on  either  side,  one  is  placed  at  the  an- 
gle of  the  temporal  bone  where  it  runs  up  between  the  occipital 
and  the  parietal.  The  other  is  in  the  temporal  fossa,  under  the 
temporal  muscle,  at  the  junction  between  the  parietal  and  the 
sphenoidal  bones.  These  two  fontanels  are  but  little  referred 
to  by  the  accoucheur  in  delivery,  as  they  are  irregular  and  in- 
distinct. The  pulsations  of  the  brain  may  be  readily  felt  through 


180  SKELETON. 

the  fontanels.  They  ossify  rapidly  after  birth,  and  are  fre- 
quently closed  completely  by  the  end  of  the  first  year ;  but  if 
there  be  an  accumulation  of  water  in  the  ventricles  of  the  brain, 
they  remain  open  for  an  indefinite  period. 

The  longest  diameter  of  a  child's  head  is  from  the  vertex  or 
posterior  extremity  of  the  sagittal  suture  to  the  chin,  and  mea- 
sures five  inches  and  a  quarter.  From  the  middle  of  the  frontal 
bone  to  the  tubercle  of  the  occipital  is  four  inches,  from  one 
parietal  protuberance  to  the  other  is  about  three  inches  and  a 
half. 

At  birth  the  os  frontis  consists,  most  commonly,  of  two  pieces, 
united  by  the  sagittal  suture.  The  parietal  bone  is  a  single 
piece,  incomplete  at  its  angles.  The  temporal  bone  consists  of 
three  pieces:  one  is  the  squamous,  the  other  is  the  petrous,  and 
the  third  is  a  small  ring  which  afterwards  constitutes  the  meatus 
externus;  it  is  deficient  in  styloid  and  mastoid  processes.  The 
os  occipitis  is  in  four  pieces:  one  extends  from  the  angle  of  the 
lambdoidal  suture  to  the  upper  edge  of  the  foramen  magnum; 
on  either  side  of  the  foramen  magnum  is  another,  with  the  con- 
dyle  growing  on  it,  and  the  cuneiform  process  is  the  fourth.  The 
ethmoid  bone  is  cartilaginous.  The  sphenoidal  bone  is  in  three 
pieces.  The  body  and  little  wings,  being  united,  form  one ;  the 
great  wing  and  the  pterygoid  process,  being  also  united,  form 
on  either  side  of  the  body  another  piece. 

At  birth  there  is  a  great  disproportion  in  size  between  the  cra- 
nium and  face.  This  disproportion  diminishes  in  the  progress 
of  life,  by  the  development  of  the  sinuses  and  of  the  alveolar 
processes  in  the  latter.  At  birth,  indeed,  there  is  no  cavity  ei- 
ther in  the  sphenoidal,  the  frontal,  or  the  upper  maxillary  bones; 
the  orbitar  and  the  palate  plates  are  very  near  each  other,  and 
the  rudiments  of  the  teeth  are  hidden  in  the  bodies  of  the  up- 
per and  lower  jaw  bone.  The  latter  consists  of  two  pieces, 
united  by  cartilage  at  the  chin,  and  its  angle  is  very  obtuse. 


HYOID  BONE.  18 i 

CHAPTER  IV. 

THE  HYOID  BONE,  (OS  HYOIDES,  HYOIDE.) 

THE  Os  Hyoides  is  placed  at  the  root  of  the  tongue,  within 
the  circle  of  the  lower  jaw.  It  is  ah  insulated  bone,  having  no 
connexion  with  any  other,  except  by  muscles  and  ligaments. 
It  is  said,  very  properly,  to  resemble  the  letter  U,  and  consists 
of  a  body  and  two  cornua. 

The  body  is  in  the  middle;  it  is  the  largest  part  of  the  bone, 
and  forms  nearly  a  semicircle.  Its  anterior  face  is  convex,  and 
its  upper  part  is  flattened  by  the  insertion  of  the  muscles  from 
the  lower  jaw.  The  posterior  face  is  concave. 

The  cornua,  one  on  either  side,  are  about  an  inch  long,  and 
are  placed  at  the  extremities  of  the  body,  being  united  to  it  by 
the  interposition  of  cartilage  and  ligamentous  fibres.  They  are 
somewhat  flattened  rather  than  cylindrical,  and  diminish  to- 
wards the  posterior  extremities,  where  they  terminate  in  a 
round  enlargement  like  a  head. 

At  the  cartilaginous  junction  of  the  cornu  and  body,  on  each 
side,  there  is  a  small  cartilaginous  body  three  or  four  lines  long, 
fastened  by  ligamentous  fibres.  It  is  frequently  found  ossified. 
This  is  the  appendix  or  lesser  cornu.  A  round  ligament  passes 
from  it  to  the  extremity  of  the  styloid  process  of  the  temporal 
bone. 

The  texture  of  this  bone  is  cellular,  with  a  thin  compact  la- 
mina externally.  M.  Portal  says,  that  he  has  found  it  carious 
from  venereal  contamination;  in  which  case,  the  patient  had 
been  afflicted  with  violent  sore  throat  and  purulent  expectora- 
tion. Sauvages  and  Valsalva  have  met  with  a  case,  where, 
from  luxation  of  the  cornu,  the  patient  spoke  with  great  diffi- 
culty. The  ligament  to  the  styloid  process  is,  in  some  rare  in- 
stances, ossified  to  a  considerable  extent,  which  produces  diffi- 
culty in  swallowing  and  in  talking. 

VOL.  I.— 16 


182  SKELETON. 

CHAPTER  V. 

OF  THE  UPPER  EXTREMITIES. 

THIS  portion  of  the  skeleton  is  divided  on  either  side  of  the 
body,  into  shoulder,  arm,  fore  arm,  and  hand. 

SECT.  I. OF  THE  SHOULDER, 

The  shoulder  consists  of-two  bones,  the  clavicle  and  the  sca- 
pula, and  occupies  the  superior,  lateral,  and  posterior  part  of  the 
thorax.     Its  shape  and  position  are  such,  that  it  augments  con- 
siderably the  transverse  diameter  of  the  upper  part  of  the  trunk, 
taken  as  a  whole:  while  the  thorax  alone,  at  this  place,  is  actu- 
ally smaller  than  it  is  below.     The  clavicle  is  longer,  in  pro- 
portion, in  the  female  than  in  the  male,  which  increases  the 
transverse  extent  of  the  shoulder,  and  gives  a  greater  space  on 
the  front  of  the  thorax  for  the  development  of  the  mammas. 
This  coincidence  between  the   length  of  the  shoulder  and  the 
development  of  the  mamma,  has  been  particularly  noticed  by 
Bichat,  who  says  that  it  is  almost  always  well  marked,  that  very 
rarely  a  voluminous  bosom  reposes  on  a  small  pectoral  space, 
or  a  small  bosom  is  found  upon  a  large  pectoral  space.     In  the 
male,  on  the  contrary,  this  diameter  of  the  trunk  is  increased 
principally  by  the  breadth  of  the  scapula,  which,  from  its  posi- 
tion on  the  thorax,  and  its  great  size,  gives  the  bulky  appear- 
ance to  this  part.     It  is  evident  that  these  modifications  in  the 
frame-work  of  the  shoulders,  are  connected  with  the  natural  des- 
tinations of  the  two  sexes.     In  woman  the  length  of  the  clavi- 
cle is  adverse  to  its  strength,  and  it  is  indistinctly  marked  by 
muscular  connexions;   whereas,  in  man  it  is  short,  strongly 
marked,  and  large.     Anatomists  who  are  fond  of  extending 
such  comparisons,  say,  also,  very  justly,  that  the  pubes,  which 
perform  the  same  office  for  the  lower  extremities  that  the  cla- 
vicles do  for  the  upper,  that  of  keeping  the  two  apart,  are,  in 
the  female,  both  smaller  and  longer  than  in  the  male;  that  their 
shape  is  not  so  favourable  to  strength  or  locomotion,  and  has  a 
special  view  towards  the  lodgement  of  the  genital  organs,  and 


THE  SHOULDERS.  183 

to  the  passage  of  the  child.  In  man  the  increased  size  of  the 
whole  skeleton,  and  the  greater  development  of  the  muscular 
system,  indicate  that  he  was  intended  for  more  laborious  exer- 
tion than  the  female. 

The  thorax  and  the  shoulder  are  connected  by  a  reciprocal 
development,  both  being  indicative,  when  large,  of  a  robust  and 
vigorous  constitution,  and  when  small,  of  a  weakly  one.  As 
both  of  these  parts  are  acted  on  by  the  same  muscles,  the  ne- 
cessity of  this  coincidence  is  sufficiently  apparent  The  height 
of  the  shoulder  depends  upon  the  scapula  alone;  its  elevation, 
therefore,  is  greater  in  males  and  in  vigorous  persons  generally, 
than  in  females  and  in  weakly  individuals.  The  direction  of 
the  shoulder  is  such,  that  the  articular  face  of  the  scapula  for 
the  os  humeri,  looks  outwards,  thereby  proving  that  the  quad- 
ruped position  in  man  is  unnatural;  for  by  it,  the  weight  of  the 
fore  part  of  the  trunk  is  directed  upon  the  back  part  of  the  cap- 
sular  ligament  of  the  joint  instead  of  upon  the  glenoid  cavity, 
as  in  quadrupeds.  This,  and  many  other  circumstances,  prove 
that  the  natural  intention  of  the  upper  extremities  in  the  human 
subject,  is  to  seize  upon  objects,  and  not  to  maintain  the  hori- 
zontal position. 


Of  the  Shoulder  Blade,  (Scapula,  Omoplate.) 

The  Scapula  is  placed  upon  the  posterior  superior  part  of  the 
thorax,  and  extends  from  the  second  to  the  seventh  rib  inclu- 
sively; its  posterior  edge  is  nearly  parallel  with  the  spinous  pro- 
cesses of  the  vertebrae,  and  not  far  from  them. 

Its  general  form  is  triangular.  It  therefore  presents  two 
faces,  of  which  one  is  anterior,  and  the  other  posterior, — three 
edges,  of  which  one  is  superior,  another  external,  and  the  third 
internal  or  posterior — and  three  angles,  of  which  one  is  supe- 
rior, another  inferior,  and  the  third  exterior  or  anterior. 

The  posterior  face  of  the  scapula,  or  its  dorsum,  is  somewhat 
convex,  when  taken  as  a  whole;  and  is  unequally  divided  by  its 
spine  into  two  surfaces  or  cavities,  of  which  the  lower  is  twice 
or  three  times  as  large  as  the  upper.  The  spine  is  a  very  large 
process  that  begins  at  the  posterior  edge  of  the  bone,  by  a  smal 
triangular  face;  rapidly  increases  in  its  elevation,  and  running 


184  SKELETON. 

obliquely  towards  the  anterior  angle,  ceases  somewhat  short  of 
it;  it  is  then  elongated  forwards  and  upwards,  so  as  to  overhang 
the  shoulder  joint,  and  to  form  the  acromion  process.  The  ca- 
vity above  the  spine  is  owing  principally  to  the  elevation  of 
the  latter,  and  is  called  the  fossa  supra-spinata;  it  is  occupied 
by  the  supra-spinatus  muscle.  The  cavity  below  the  spine  is 
the  fossa  infra-spinata,  and  is  for  the  infra-spinatus  muscle:  it  is 
bounded  below  by  a  rising  of  the  external  margin  of  the  bone. 
The  middle  of  this  fossa  presents  a  swell  or  convexity,  which 
is  a  portion  of  the  general  convexity  presented  by  the  posterior 
face  of  the  bone.  The  spine  of  the  scapula  is  always  promi- 
nent in  the  outline  of  the  shoulder,  and  has  a  well  secured  base 
along  the  whole  of  its  attachment  to  the  bone,  to  where  it  ter- 
minates in  the  acromion  process.  It  leans  upwards,  and  from 
the  increased  breadth  of  its  summit,  is  concave  both  above  and 
below.  The  summit  itself  is  somewhat  rough,  and  has  inserted 
into  its  superior  margin  the  trapezius  muscle,  while  the  infe- 
rior margin  gives  origin  to  the  deltoid.  The  little  triangular 
face  at  the  commencement  of  the  spine  is  made  by  the  tendon 
of  the  trapezius  muscle  gliding  over  it.  The  acromion  process 
arises  from  the  spine  by  a  narrow  neck,  is  triangular,  nearly 
horizontal,  and  overhangs  the  glenoid  cavity,  being  elevated 
about  one  inch  above  it.  It  is  slightly  convex  above  and  con- 
cave below:  the  external  and  the  internal  margins  are  the  long- 
est. The  posterior  margin  is  continuous  with  the  inferior  edge 
of  the  spine  of  the  scapula;  and  the  internal  is  on  a  level  with 
the  clavicle.  At  the  fore  extremity  of  the  internal  margin,  is  a 
small,  oval,  articular  face,  by  which  the  acromion  unites  with 
the  clavicle.  The  margins  of  the'  acromion,  with  the  excep- 
tion of  the  internal,  are  rough,  and  give  origin  to  the  deltoid 
muscle. 

The  anterior  or  costal  face  of  the  scapula  is  concave,  and 
obtains  the  name  of  the  sub-scapular  fossa  or  venter.  It  is  oc- 
cupied by  the  sub-scapular  muscle;  the  divisions  of  which,  by 
leaving  deep  interstices  between  them,  produce  corresponding 
ridges  upon  the  bone,  that  run  obliquely  upwards  and  outwards. 
Along  the  whole  posterior  margin  of  this  face  of  the  scapula, 
is  inserted  the  serralus  major  anticus. 


THE  SHOULDERS.  185 

The  posterior  or  vertebral  margin  of  the  scapula  is  the  long- 
est of  the  three,  and  is  called  the  base.  It  is  not  perfectly 
straight,  but  somewhat  rounded,  especially  above  the  spinous 
process;  and  has  there  varied  degrees  of  obliquity  in  different 
persons.  This  margin,  below  the  spine,  receives  the  rhomboi- 
deus  major  muscle,  and  above  the  spine,  the  levator  scapulae; 
at  the  part  between  the  other  two,  the  rhomboideus  minor  is 
inserted. 

The  external  or  axillary  margin  of  the  scapula,  also  called 
the  inferior  costa,  is  much  the  thickest  of  the  three.  A  superfi- 
cial fossa  placed  somewhat  posteriorly,  forming  the  inferior 
boundary  of  the  fossa  infra-spinata,  begins  about  two  inches 
from  its  inferior  extremity,  and  running  up  to  the  neck  of  the 
bone,  lodges  the  teres  minor  muscle.  On  the  exterior  face  of 
the  inferior  angle  is  a  flat  surface,  from  which  the  teres  major 
muscle  and  a  slip  of  the  latissimus  dorsi  arise.  At  the  fore 
part  of  this  surface  the  inferior  costa  is  elongated  into  a  kind 
of  process.  Just  below  the  glenoid  cavity  is  a  small  ridge  for 
the  origin  of  the  long  hea,d  of  the  triceps  muscle. 

The  superior  margin  or  costa  of  the  scapula,  is  the  shortest 
and  thinnest  of  the  three,  and  is  terminated  in  front  by  the  co- 
racoid  notch  between  it  and  the  coracoid  process.  The  notch 
is  converted  into  a  hole  by  a  ligament,  in  the  living  state,  and 
through  it  pass  the  upper  scapular  nerve  and  blood  vessels. 

The  glenoid  cavity  for  articulating  with  the  os  humeri,  sup- 
plies the  place  of  the  anterior  angle  of  the  scapula.  It  is  very 
superficial,  and  ovoidal,  with  the  small  end  upwards.  Just  at 
the  upper  end  is  a  small  flat  surface,  from  which  the  long  head 
of  the  biceps  arises.  The  glenoid  cavity  is  fixed  on  the  cervix, 
as  it  is  called,  at  which  a  general  increase  in  the  thickness  of  the 
bone  occurs,  in  order  to  give  a  strong  foundation  to  this  cavity. 
From  the  superior  part  of  the  cervix  arises  the  coracoid  pro- 
cess, the  base  of  it  being  bounded  in  front  by  the  glenoid  cavi- 
ty, and  behind  by  the  coracoid  notch.  The  base  rises  upwards 
and  inwards  for  half  an  inch,  and  what  remains  of  the  process, 
then,  runs  horizontally  inwards  and  forwards,  to  become  small- 
er, and  terminate  in  a  point.  This  point  is  advanced  beyond 

16* 


186  SKELETON. 

the  glenoid  cavity,  about  an  inch  from  its  internal  margin.  The 
upper  surface  of  the  coracoid  process  is  rough  and  undulated; 
below  it  is  concave,  forming  an  arch  under  which  passes  the 
sub-scapularis  muscle.  On  the  clavicular  side  of  its  base  is  a 
tuberosity,  from  which  arises  the  conoidal  ligament.  The  ex- 
tremity is  marked  by  three  surfaces :  the  interior  is  for  the  in- 
sertion of  the  pectoralis  minor,  the  middle  for  the  origin  of  the 
coraco-brachialis,  and  the  external  for  that  of  the  short  head  of 
the  biceps.  The  acromial  margin  of  the  coracoid  process  gives 
origin  to  the  triangular  ligament  of  the  scapula,  which  is  in- 
serted into  the  acromion  just  below  the  face  for  the  clavicle. 

The  scapula  is  composed  of  cellular  and  compact  substance. 
The  two  laminae  of  the  latter  are  in  contact  in  the  fossa  supra- 
spinata,  and  infra-spinata;  from  which  cause  the  bone  is  diapha- 
nous at  these  points* 


Of  the  Clavicle,  (Clamcula,  Clavicule.) 

The  Clavicle  is  a  long  bone,  situated  transversely  at  the  up- 
per front  part  of  the  thorax,  and  extends  from  the  superior  ex- 
tremity of  the  sternum  to  the  acromion  of  the  scapula.  It  is 
cylindrical  in  its  middle  third,  flattened  at  its  external,  and 
prismatic  or  triangular  at  its  sternal  extremity.  Besides  being 
shorter,  it  is  more  crooked  and  robust  in  man  than  in  woman, 
and  different  individuals  present  it  under  considerable  varieties 
of  curvature.  The  sternal  two-thirds  of  it  are  convex  in  front, 
and  concave  behind,  while  the  humeral  third  is  concave  in 
front,  and  convex  behind:  this  double  curvature  induces  anato- 
mists to  compare  it  with  the  letter  S,  though  it  is  by  no  means 
so  crooked. 

We  have  to  consider  its  superior  and  inferior  face,  its  ante- 
rior and  posterior  edge,  and  the  two  extremities.  The  superior 
face  is  smooth,  and  does  not  present  any  marks  of  importance 
excepting  a  depression  near  the  sternum,  for  the  origin  of  the 
sterno-cleido  mastoid  muscle.  The  inferior  face,  near  the  ster- 
nal end,  has  a  rough  surface,  to  which  is  attached  the  costo- 
clavicular  or  rhomboid  ligament:  about  fifteen  lines  from  the 
humeral  extremity  is  a  rough  tubercle  for  the  attachment  of  the 
coraco-clavicular  or  conoid  ligament.  Between  the  two  ends, 


THE  ARM.  187 

a  superficial  fossa  is  extended  for  lodging  the  sub-clavius  mus- 
cle. The  sternal  two-thirds  of  the  anterior  margin  are  marked 
by  the  origin  of  the  pectoralis  major;  it  is  there  thick:  the  other 
part  of  this  margin  is  thinner,  and  gives  origin  to  the  deltoid 
muscle.  The  posterior  margin  presents,  near  its  middle,  one  or 
more  foramina  for  the  nutritious  vessels.  The  triangular  inter- 
nal end  of  the  clavicle  is  unequal  where  it  joins  the  sternum, 
and  is  elongated  considerably  at  its  posterior  inferior  corner. 
The  external  flat  end  presents  at  its  extremity  a  small  oval  face, 
corresponding  with  that  on  the  acromion  scapulae. 

This  bone  is  very  strong  from  the  abundance  of  its  condensed 
lamellated  structure;  but,  like  other  round  bones,  the  cellular 
matter  predominates  at  its  extremities. 


SECT.  n. — OF  THE  ARM,  (Os  Humeri,  ISHumerus.) 

The  arm  extends  from  the  shoulder  to  the  elbow,  and  has  but 
one  bone  in  it,  the  os  humeri.  The  latter,  in  its  general  ap- 
pearance, is  cylindrical,  with  an  enlargement  of  both  extremi- 
ties; the  superior  end  presents  a  general  swell,  while  the  infe- 
rior is  flattened  out. 

The  superior  extremity  of  the  os  humeri,  which  is  also  called 
its  head,  is  very  regularly  hemispherical,  and  has  its  axis  di- 
rected obliquely  upwards  and  backwards,  to  apply  itself  with 
more  facility  to  the  glenoid  cavity  of  the  scapula.  The  base  on 
which  the  head  reposes  is  termed  neck,  it  is  riot  more  than  four 
or  five  lines  long,  and  is  marked  off  by  a  superficial  furrow, 
surrounding  the  bone.  This  furrow  is  more  conspicuous  above, 
where  it  separates  the  head  from  two  knobs  called  the  tubero- 
sities. 

One  of  these  tuberosities,  the  external,  being  placed  beneath 
the  acromion  scapulae,  is  much  larger  than  the  other,  and  bears 
on  its  upper  face  the  marks  of  the  tendinous  insertion  of  three 
muscles.  The  most  internal  mark  is  for  the  supra-spinatus 
scapulae,  the  middle  for  the  infra-spinatus,  and  the  external,  or 
posterior,  for  the  teres  minor.  The  smaller  tuberosity  is  inter- 
nal, and  placed  on  a  line  with  the  coracoid  process;  it  has  but 
one  mark,  and  that  is  on  its  upper  face,  for  the  tendinous  inser- 
tion of  the  sub-scapularis  muscle.  The  two  tuberosities  are 


188  SKELETON. 

separated  by  a  deep  fossa,  named  bicipital,  from  its  lodging  the 
tendon  of  the  long  head  of  the  biceps  muscle.  This  fossa  is 
continued,  faintly,  for  some  inches  down  the  os  humeri;  its 
lower  part  being  bounded,  externally,  by  a  rough  ridge,  indi- 
cating the  insertion  of  the  pectoralis  major,  and  internally  by 
another  ridge,  not  quite  so  strong  or  rough,  indicating  the  in- 
sertion of  the  teres  major  and  latissimus  dorsi. 

The  body  of  the  os  humeri  is  the  part  extended  between  its 
extremities.  The  superior  half  presents  a  more  cylindrical  ap- 
pearance than  the  inferior,  which  is  rather  triangular.  On  the 
middle  of  the  bone,  externally,  two  inches  below  the  insertion 
of  the  pectoralis  major,  exists  a  triangular  elevation  into  which 
the  deltoid  muscle  is  inserted.  At  the  internal  margin  of  the 
bone,  and  on  a  line  with  the  latter,  is  the  insertion  of  the  coraco- 
brachialis  muscle;  and  between  the  two  is  the  orifice  of  the  canal 
for  the  nutritious  artery.  The  front  of  the  os  humeri,  in  its 
lower  half,  is  flattened  on  each  side  down  to  its  inferior  end;  on 
these  surfaces  is  placed  the  brachialis  internus  muscle.  On  a 
line  with  the  posterior  end  of  the  greater  tuberosity,  and  a  lit- 
tle below  it,  an  elevation  is  formed  for  the  origin  of  the  second 
head  of  the  triceps  extensor  cubiti.  The  posterior  face  of  the 
bone  is  flattened  from  this  point  down  to  its  lower  extremity, 
and  accommodates  the  last  named  muscle. 

The  articular  surface  for  the  elbow  joint  is  very  irregularly 
cylindrical.  The  part  that  joins  the  radius,  presents  itself  as  a 
small  hemispherical  head,  placed  on  the  front  of  the  bone,  and 
with  its  axis  looking  forwards.  Just  above  it,  in  front,  is  a 
small  depression  for  the  head  of  the  radius  in  its  flexions.  The 
surface  which  is  in  contact  with  the  ulna,  is  more  cylindrical, 
but  still  irregularly  so ;  for  its  middle  is  depressed,  wrhile  the 
sides  are  elevated:  the  internal  side  is  much  broader  and  more 
elevated  than  the  external.  The  lesser  sigmoid  cavity  is  just 
above  the  front  of  the  ulnar  articular  surface,  and  receives  the 
coronoid  process.  The  greater  sigmoid  cavity  is  in  a  corre- 
sponding place  behind,  and  receives  the  olecranon  process:  the 
bone  where  it  separates  these  cavities  is  very  thin;  sometimes 
it  is  even  deficient. 


THE  FORE  ARM.  189 

The  external  condyle  is  just  above  the  radial  articular  surface ; 
it  is  continuous  with  a  ridge  of  three  or  four  inches  long,  form- 
ing the  external  margin  of  the  bone,  and  from  it,  and  the  ridge 
together,  arise  the  extensor  muscles  of  the  fore  arm  and  hand. 
The  ridge,  itself,  is  bounded,  above,  by  a  small  spiral  fossa,  de- 
scending downwards  and  forwards,  made  by  the  spiral  artery 
and  the  muscular  spiral  nerve.  The  internal  condyle  is  placed 
just  above  the  internal  margin  of  the  ulnar  articular  surface  :  it 
is  much  more  prominent  and  distinct  than  the  external,  and  may 
be  readily  felt  beneath  the  skin.  A  ridge  also  leads  from  it, 
and  extends  upwards  as  high  as  the  insertion  of  the  coraco- 
brachialis,  but  it  is  by  no  means  so  elevated  as  the  external 
ridge,  though  it  is  much  longer.  From  the  internal  condyle, 
and  the  adjoining  part  of  the  ridge,  arise  the  flexor  muscles  of 
the  hand  and  fore  arm. 

The  os  humeri  is  composed  of  compact  and  cancellated  sub- 
stance; the  latter  predominates  at  the  extremities,  and  the  former 
in  the  body. 

SECT.  III. OF  THE  FORE  ARM. 

The  fore  arm  is  placed  between  the  arm  and  the  hand,  and 
consists  in  two  straight  bones,  the  Ulna  and  the  Radius,  of 
which  the  former  is  on  the  same  side  with  the  little  finger,  and 
the  latter  on  that  of  the  thumb. 


Of  the  Ulna,  (Cubitus.} 

The  ulna,  though  nearly  strait,  is  not  wholly  so.  It  is 
much  larger  at  the  upper  than  at  the  lower  extremity,  and  in  its 
general  features  is  triangular.  It  has  to  be  considered  in  its 
humeral  and  carpal  extremities,  and  in  its  body. 

The  humeral,  or  upper  extremity,  presents  the  olecranon  pro- 
cess at  its  termination  ;  the  coronoid  a  little  below  and  in  front; 
the  greater  sigmoid  cavity  between  the  two;  and  the  lesser  sig- 
moid  on  the  radial  surface  of  the  coronoid. 

The  olecranon  process  is  rough  on  its  upper  face,  for  the  in- 


190 


SKELETON. 


sertion  of  the  triceps  muscle,  and  terminates  in  front  in  a  sharp 
edge  and  point,  which  are  received  into  the  greater  sigmoid  ca- 
vity of  the  os  humeri.  The  coronoid  process  is  a  triangular 
sharp  ridge,  much  elevated,  and  having  a  large  base ;  on  the 
lower  front  of  the  latter  is  a  roughness  for  the  insertion  of  the 
brachialis  internus  muscle.  The  greater  sigmoid  cavity  forms 
all  the  articular  surface  between  the  margins  of  the  two  pro- 
cesses. It  is  divided,  transversely,  at  its  bottom,  by  a  superfi- 
cial roughness,  which  distinguishes  the  olecranon  from  the  co- 
ronoid portion  of  it.  Besides  which,  a  rising  exists  in  its  verti- 
cal length,  which  is  received  into  the  corresponding  depression 
of  the  os  hurneri.  The  lesser  sigmoid  cavity  has  its  surface 
continuous  with  that  of  the  greater,  and  presents  itself  as  a  small 
semi-cylindrical  concavity,  for  articulating  with  the  side  of  the 
head  of  the  radius.  A  small  fossa,  for  fatty  matter,  exists  just 
above  it. 

The  carpal,  or  lower  extremity  of  the  ulna,  presents,  on  the 
side  of  the  little  finger,  a  process  of  variable  length,  the  sty- 
loid,  from  which  arises  the  internal  lateral  ligament  of  the  wrist. 
At  the  radial  side  of  this  process  is  an  articular  face  or  small 
head,  one"  surface  of  which  looks  towards  the  wrist,  and  the 
other  is  in  contact  with  the  radius,  being  semi-cylindrical.  On 
the  back  of  the  ulna,  between  the  styloid  process  and  this  head, 
is  a  groove  for  a  passage  of  the  extensor  carpi  ulnaris. 

The  body  of  the  ulna  is  triangular,  in  consequence  of  three 
ridges,  which  extend  from  the  brachial  to  the  carpal  extremity. 
The  most  prominent  of  these  ridges  is  on  its  radial  side,  and, 
beginning  al  the  posterior  end  of  the  lesser  sigmoid  cavity,  con- 
tinues very  distinct  almost  to  the  lower  end;  it  then,  however, 
gradually  subsides.  From  it  arises  the  interosseal  ligament. 
Within  this  ridge,  on  the  anterior  or  palmar  face  of  the  bone, 
is  another,  more  rounded,  which,  beginning  at  the  internal  mar- 
gin of  the  coronoid  process,  extends  down  to  the  styloid  pro- 
cess. For  the  greater  part  of  its  length  it  gives  origin  to  the 
flexor  profundus  digitorum,  but  just  above  the  carpus,  the  pro- 
nator  quadratus  arises  from  it.  The  third  ridge  begins  at  the 
external  margin  of  the  olecranon,  and  runs  in  a  serpentine  way 
to  the  inferior  end  of  the  ulna,  but  becomes  almost  indistinct  at 


THE  FORE  ARM.  191 

its  lower  part.  To  the  upper  fourth  of  this  ridge,  is  attached 
the  anconeus  muscle,  which  reposes  in  a  hollow  between  it  and 
the  beginning  of  the  first  or  outer  ridge.  To  the  beginning  of 
this  latter  ridge,  is  attached  the  supinator  radii  brevis  muscle. 
On  the  posterior  surface  of  the  bone,  just  below  the  olecranon, 
is  a  long  sub-cutaneous  triangular  face  on  which  we.  lean. 

The  three  ridges  of  the  ulna  divide  it  into  as  many  surfaces, 
which  are  each  modified  by  the  muscles  lying  upon  them.  The 
anterior  surface  presents,  just  above  the  middle  of  the  bone,  the 
canal  for  the  nutritious  artery,  running  obliquely  upwards. 

The  body  of  the  ulna  is  compact,  the  extremities,  and  more 
abundantly  the  upper,  are  cellular. 

Of  the  Radius,  (Radius.) 

The  radius  is  shorter  than  the  ulna,  is  placed  on  its  external 
side,  and  extends  from  the  os  humeri  to  the  wrist.  It  is  smaller 
at  the  humeral  than  at  the  carpal  extremity,  and  though  nearly 
straight  is  somewhat  convex  outwardly.  It  is  to  be  considered 
in  its  extremities  and  body. 

The  superior  or  humeral  extremity  presents  a  cylindrical 
head,  which  bears  all  around  it  the  marks  of  a  cartilaginous  in- 
crustation, broader  on  the  cubital  than  on  the  other  side.  The 
broader  part  plays  in  the  lesser  sigmoid  cavity  of  the  ulna,  while 
the  other  is  in  contact  with  the  annular  ligament.  A  superficial 
fossa  also  exists  on  the  upper  surface  of  this  head,  which  re- 
ceives the  convexity  of  the  articular  face  of  the  external  con- 
dyle  of  the  os  humeri.  The  head  of  the  radius  is  placed  upon 
a  narrow  part  called  the  neck,  of  about  half  an  inch  in  length. 
Immediately  below  the  neck,  on  the  ulnar  side,  is  a  rough  pro- 
.  tuberance  or  tubercle,  the  bicipital,  for  the  insertion  of  the  bi- 
ceps flexor  cubiti. 

The  lower  or  carpal  extremity  of  the  bone,  is  augmented  con- 
siderably in  volume,  and  is  flattened  out  transversely.  The 
carpal  surface  presents  a  long  superficial  cavity,  bounded  ex- 
ternally by  the  styloid  process,  from  which  proceeds  the  exter- 
nal lateral  ligament;  and  ending  on  its  ulnar  side,  by  a  small 


192  SKELETON. 

cylindrical  concavity,  for  receiving  the  lower  end  of  the  ulna. 
The  former  or  superficial  cavity  is  divided  into  two  by  a  slight 
ridge  in  its  short  diameter ;  the  division  next  the  styloid  pro- 
cess receives  the  scaphoid  l?one,  and  the  other  the  os  lunare. 
At  this  extremity  also  a  ridge  exists  on  the  front  of  the  bone 
for  forming  the  margin  of  the  articular  face,  and  giving  origin 
to  the  capsular  ligament.  The  posterior  and  external  faces  of 
the  bone.,  here,  are  rendered  irregular  by  several  grooves  and 
ridges.  The  large  groove  next  to  the  cylindrical  concavity  for 
the  ulna,  transmits  the  tendons  of  the  extensor  communis  digi- 
torum  and  indicator,  also  the  tendon  of  the  extensor  major  pol- 
licis,  which  forms  a  channel  somewhat  distinct,  and  on  the  sty- 
loid side  of  the  groove.  Next  to  this  is  another  large  groove  for 
the  tendons  of  the  extensor  carpi  radialis  brevior  and  loagior ; 
and  on  the  styloid  side  of  the  radius  is  the  third  groove  for 
transmitting  the  tendon  of  the  extensor  minor  pollicis,  and  of 
the  extensor  ossis  metacarpi  pollicis.  The  anterior  margin  of 
this  groove  is  formed  by  a  small  spine  or  ridge,  into  which  is 
inserted  the  tendon  of  the  supinator  radii  longus. 

The  body  of  the  radius  is  somewhat  triangular,  and  therefore 
presents  three  ridges.  One,  on  its  ulnar  side,  extends  from  the 
bicipital  protuberance  to  the  lower  end,  and  gives  origin  to  the 
interosseous  ligament:  it  is  sharp  and  well  marked.  Another, 
on  the  outer  or  styloid  margin  of  the  bone,  also  begins  at  the 
bicipital  protuberance,  and  terminates  in  the  styloid  process. 
The  upper  part  of  this  ridge  is  curved,  has  the  supinator  brevis 
inserted  into  it,  and  a  portion  of  the  flexor  digitorum  sublimis 
arising  from  it ;  at  its  lower  part  the  pronator  quadratus  is  in- 
serted. The  third  ridge  is  on  the  posterior- face  of  the  radius, 
and,  arising  insensibly  from  below  its  neck,  is  principally  con- 
spicuous in  the  middle  third  of  the  bone:  it  runs  down,  however, 
to  the  carpal  extremity,  and,  becoming  more  prominent  there, 
separates  the  two  larger  grooves  from  each  other.  This  ridge 
is  shorter,  and  not  so  elevated  as  the  other  two. 

These  three  ridges  form  as  many  surfaces  to  the  radius,  of 
which  the  anterior  augmenting  gradually  in  its  descent,  affords 
attachment  to  the  flexor  longus  pollicis  above,  and  to  the  pro- 
nator quadratus  below;  at  its  upper  part  is  a  canal,  slanting  up- 
wards, for  the  nutritious  artery.  The  posterior  surface  has  the 


THE  HAND.  193 

extensor  muscles  of  the  thumb  and  the  indicator  lying  upon  it. 
The  external  surface  presents  a  roughness,  just  above  its  mid- 
dle, for  the  insertion  of  the  pronator  teres ;  and  below  it  is  co- 
vered by  the  radial  extensors,  which  are  crossed  by  the  exten- 
sor metacarpi  pollicis  and  the  extensor  minor. 

The  body  of  the  radius  is  compact ;  its  extremities  are  cel- 
lular. 


SECT.  IV. OF  THE  HAND. 

The. hand  consists  of  carpus,  metacarpus,  and  phalanges,  and 
has  in  its  composition  twenty-seven  bones,  to  which  number 
may  be  added  the  two  sesamoids. 


Of  the  Carpus,  (Carpe.) 

The  carpus,  or  wrist,  is  next  to  the  bones  of  the  fore  arm. 
Eight  bones  compose  it,  which  are  arranged  into  two  rows,  one 
adjoining  the  fore  arm,  and  the  other  the  metacarpus : — they 
are  called  first  and  second  rows.  These  bones  present  very 
diversified  forms,  and  a  number  of  articular  faces,  which  ren- 
der them  difficult  to  be  distinguished  from  each  other. 

The  first  or  antibrachial  row  has  in  it  the  os  scaphoides,  lu- 
nare,  cuneiforme,  pisiforme.  The  second  or  metacarpal  row 
has  in  it  the  os  trapezium,  trapezoides,  magnum,  and  unci- 
forme. 

Of  the  Scaphoides,  (Scaphoide,) 

This  bone  is  on  the  styloid  half  of  the  end  of  the  radius,  and 
is  distinguishable  in  a  set  by  its  greater  length.  It  is  convex 
above  and  concave  below.  The  convexity  forms  only  a  half 
of  its  upper  surface,  the  other  half  being  rough,  and  making  a 
knob  at  its  extremity.  The  concavity  on  the  lower  surface  is 
large  enough  to  receive  the  end  of  a  finger.  Between  the 
concavity  and  the  convexity,  and  on  the  dorsal  surface  of  the 
bone,  at  its  outer  end,  is  a  second  convexity,  of  an  oblong  shape. 
Between  the  two  convexities  is  a  small  fossa  for  the  capsular 
ligament.  The  palmar,  or  anterior  face,  shows  a  crook  in  the 

VOL.  L— 17 


194  SKELETON.  - 

bone.  The  knobbed  extremity  projects  beyond  the  styloid  pro- 
cess of  the  radius.  The  other  extremity,  which  is  narrow,  joins 
the  os  lunare. 

Of  the  Lunare,  (Semilunare.) 

This  bone  is  at  the  ulnar  side  of  the  preceding,  and  may  be 
distinguished  by  the  semi-lunated  shape  of  the  surface  joining 
the  scaphoides.  Its  upper  surface  is  convex  where  it  articulates 
with  the  radius;  the  lower  face  is  concavely  cylindrical.  The 
ulnar  side  is  a  plain  surface  which  joins  the  os  cuneiforme.  Its 
dorsal  side  is  rather  thinner  than  its  palmar. 


Of  the  Cuneiforme  or  Pyramidale,  (Pyramidal.) 

This  bone  is  placed  at  the  ulnar  side  of  the  last,  and  may  be 
distinguished  by  its  representing  somewhat  a  triangular  pyra- 
mid. The  surface  next  the  lunare  is  plane,  but  the  other  ex- 
tremity, being  the  boundary  of  the  wrist  in  that  direction,  is 
rough.  Above,  it  presents  a  small  convexity,  adjoining  the 
surface  for  the  lunare,  whereby  it  enters  partially  into  the  upper 
wrist  joint.  Its  inferior  surface  is  concavo-convex,  the  con- 
vexity being  towards  the  ulnar  end.  On  its  palmar  side  it  pre- 
sents a  circular  plane  surface  for  the  os  pisiforme. 

Of  the  Pisiforme,  (Pisiforme.) 

This  bone  is  placed  on  the  front  or  palmar  surface  of  the  last, 
and  may  be  distinguished  by  its  being  smaller  than  any  other 
in  the  carpus,  by  its  spheroidal  shape,  and  by  its  presenting  but 
one  articular  face,  which  corresponds  with  one  on  the  cunei- 
forme. It  is  always  so  prominent  as  to  be  felt,  without  difficulty, 
at  the  ulnar  extremity  of  the  wrist,  and  is  very  moveable. 


Of  the  Trapezium,  (Trapeze.) 

This  bone  is  placed  at  the  radial  end  of  the  second  row;  its 
shape  is  exceedingly  irregular,  but  it  may  be  generally  distin- 
guished by  being  a  bone  of  the  third  magnitude  as  regards  the 
second  row.  It  is  better  for  the  student  to  find  out  first  the 


THE  HAND.  195 

surface  by  which  it  articulates  with  the  metacarpal  bone  of  the 
thumb,  which  he  can  do  in  a  short  time  by  a  comparison  of  the 
surfaces  of  the  two  bones.  This  being  successful,  will  estab- 
lish a  clew  to  the  other  surfaces,  and  to  the  relative  position  of 
the  bone.  The  thumb  surface  is  a  concave  cylindrical  trochlea, 
placed  on  the  radial  side  of  the  trapezium,  and  looking  down- 
wards and  outwards.  On  the  reversed  or  upper  side  is  a  small 
concavity,  which  receives  the  dorsal  convexity  of  the  scaphoid 
bone.  Continuous  with  this  concavity  is  another  on  the  ulnar 
side,  which  receives  a  corresponding  convexity  of  the  trape- 
zoides.  Between  this  concavity  and  the  one  for  the  thumb  is 
a  small  plane  surface,  by  which  the  trapezium  articulates  par- 
tially with  the  metacarpal  bone  of  the  fore  finger.  The  dorsal 
face  is  rough  and  unequal.  The  palmar  face  is  unequally  di- 
vided by  a  high  ridge  or  process,  at  the  ulnar  side  of  whose 
root  is  a  deep  fossa  for  the  tendon  of  the  flexor  carpi  radialis. 

Of  the  Trapezoides,  (Trapezoide.) 

It  is  placed  at  the  ulnar  side  of  the  last  bone,  and  is  the 
smallest  in  the  second  row.  There  is  no  liability  of  confound- 
ing it  with  any  other  bone  of  the  carpus,  as  it  is  the  least  of 
any,  excepting  the  pisiforme.  The  greater  difficulty  is  the  ad- 
justment of  it  in  the  separated  bones:  the  following  rule,  how- 
ever, will  serve.  It  is  surrounded  by  articular  faces  on  its  sides, 
but  the  dorsal  surface  presents  a  broad  base,  while  the  palmar 
extremity  is  reduced  in  siz.e.  Holding  the  bone  with  a  refe- 
rence to  these,  it  will  be  observed  that  one  side  is  very  crook- 
ed and  concave,  while  the  reversed  or  opposite  one  is  convex. 
The  latter  fits  against  the  surface  of  the  trapezium  which  has 
been  indicated,  while  the  former  embraces  the  side  of  the  os 
magnum  just  below  its  head.  The  metacarpal  surface  of  the 
trapezoides  is  long  and  elevated  in  its  middle  for  being  received 
into  the  root  of  the  metacarpal  bone  of  the  fore  finger,  while 
the  upper  surface  presents  a  long  concavity  for  receiving  a  part 
of  the  dorsal  convexity  of  the  scaphoides. 

Of  the  Magnum,  (Grand  Os.) 

It  is  placed  at  the  ulnar  side  of  the  trapezoides,  and,  from  its 
being  larger  than  any  other  bone  in  the  carpus,  will  scarcely 


196  SKELETON. 

be  mistaken.  Its  ulnar  side  is  flat,  and  presents  a  plane  surface 
for  articulating  with  the  unciforme.  The  radial  side  is  uneven 
and  rather  indistinctly  marked  where  it  joins  the  trapezoides, 
but  the  latter  surface  will  be  found  near  the  middle  of  this  side 
just  below  the  head.  The  upper  surface  of  the  magnum  is 
formed  into  a  spherical  head,  the  radial  side  of  which  reposes 
in  the  concavity  of  the  scaphoides,  while  the  ulnar  side  is  in  the 
concavity  of  the  lunare.  Its  metacarpal  surface  is  triangular, 
convex,  and  winding,  by  which  it  joins  the  metacarpal  bone  of 
the  middle  finger.  On  the  radial  side  of  this  surface  is  a  small 
one  continuous  with  it,  whereby  the  magnum  articulates  par- 
tially with  the  metacarpal  bone  of  the  fore  finger.  The  poste- 
rior or  dorsal  face  is  broad,  while  the  palmar  is  more  narrow. 


Of  the  Unciforme,  (Os  Crochu.) 

It  is  placed  at  the  ulnar  side  of  the  magnum,  is  nearly  of  the 
same  size,  but  readily  distinguishable  from  it  by  its  long  crooked 
process  as  well  as  by  its  peculiar  shape.  Its  radial  side  is  plane 
where  it  joins  the  magnum;  the  reversed  or  ulnar  side  is  brought 
to  a  thin  edge.  The  metacarpal  surface  presents  two  distinct 
concavities ;  the  one  next  to  the  ulnar  edge  is  for  the  metacarpal 
bone  of  the  little  finger,  and  the  other  for  that  of  the  ring  finger. 
The  upper  surface  is  convex  and  winding,  having  its  ulnar  mar- 
gin almost  touching  the  surface  of  the  metacarpal  bone  of  the 
little  finger.  The  most  considerable  portion  of  the  upper  sur- 
face reposes  upon  the  cuneiform,  and  the  remainder  upon  a 
part  of  the  concavity  of  the  lunare.  The  posterior  face  is  broad 
and  rough,  while  the  palmar  is  narrower.  From  the  ulnar  side 
of  the  latter,  projects  the  unciforme  process  already  alluded  to. 

The  two  ranges  of  carpal  bones,  thus  shaped,  present,  when 
articulated  or  united  together,  an  oblong  body,  the  greatest  dia- 
meter of  which  is  transverse.  Its  posterior  face  is  semi-cylin- 
drical and  arched,  while  the  anterior  face  is  concave  for  the 
passing  of  the  flexor  tendons.  Two  protuberances  are  found  on 
each  extremity  of  the  palmar  surface.  Those  at  the  ulnar  end 
are  the  pisiforme,  and  the  unciform  process  of  the  unciforme; 
those  at  the  radial  end  are  the  protuberance  at  the  radial  end  of 


THE  HAND.  197 

the  scaphoides  and  the  sort  of  unciform  process  from  the  trape- 
zium bounding  the  radial  margin  of  its  groove.  These  several 
prominences  may,  with  a  little  attention.,  be  readily  distinguished 
beneath  the  skin.  The  superior  face  of  the  carpus,  which  ar- 
ticulates with  the  lower  end  of  the  radius  and  ulna,  presents  an 
oblong  convex  head  formed  by  the  scaphoides,  the  lunare,  and 
very  partially  by  the  cuneiforme.  The  inferior  face  of  the  car- 
pus presents  a  very  diversified  surface,  subdivided  into  five  dis- 
tinct ones,  each  of  which  is  fashioned  according  to  the  shape 
of  the  metacarpal  bone  with  which  it  has  to  articulate. 

The  central  joint  of  the  wrist,  formed  between  the  two  rows 
of  bones,  is  very  deserving  of  attention.  The  first  row  is  con- 
vex on  its  radial  end,  the  convexity  being  formed  on  one  half 
of  the  scaphoides:  to  the  ulnar  side  of  this  there  is  a  deep  con- 
cavity formed  by  the  other  half  of  the  scaphoides, — by  the  lu- 
nare and  the  cuneiforme.  The  upper  surface  of  the  second  row 
fits  very  accurately  upon  the  lower  surface  of  the  first:  its  ra- 
dial end  is,  therefore,  a  concavity  formed  by  the  trapezium  and 
trapezoides,  which  receives  the  convexity  of  the  scaphoid;  then 
a  very  large  prominent  head  is  formed  by  the  magnum  and 
unciforme,  and  received  into  the  concavity  of  the  first  row. 
The  magnum  reposes  upon  the  scaphoides  and  part  of  the  lu- 
nare, the  unciforme  upon  the  remainder  of  the  lunare,  and  the 
whole  of  the  cuneiforme.  The  carpal  bones  consist  of  cellular, 
matter  enclosed  by  condensed  lamellated  substance. 


Of  the  Metacarpus-., 

The  metacarpus,  is  situated  between  the  carpus  and  the  pha- 
langes of  the  fingers  and  thumb.  It  consists  of  five  bones,  one 
for  the  thumb  and  one  for  each  finger.  The  latter  are  parallel 
or  nearly  so  with  each  other;  but  the  first  diverges  considerably, 
and  is  so  placed  as  to  traverse  the  others  in  front  during  its 
motions.  These  bones  are  rounded  in  their  middle,  and  enlarged 
at  their  extremities.  That  of  the  thumb  is  the  shortest,  the 
others  decrease  successively  in  length  from  the  fore  to  the  lit- 
tle finger* 

17* 


198  SKELETON. 

Of  the  First  Metacarpal  Bone,  or  that  of  the  Thumb. — It  is 
placed  upon  the  trapezium:  and  besides  being  the  shortest,  is 
also  the  thickest  of  any.  Its  upper  end  is  cylindrical  and 
slightly  concave  from  side  to  side,  to  present  a  fit  surface  to 
the  trapezium.  Its  lower  end  is  slightly  convex,  and  elongated 
in  front  into  a  trochlea,  on  either  side  of  which  reposes  a  sesa- 
moid  bone.  The  posterior  face  of  its  body  is  flat  and  straight; 
the  anterior  is  concave  in  its  length,  and  is  divided  into  two 
surfaces  by  a  middle  ridge.  A  roughness  exists  on  either  side, 
at  its  lower  end,  for  the  attachment  of  the  lateral  ligament. 

Of  the  Second  Metacarpal  Bone,  or  that  of  the  Fore  Finger. — 
The  greater  length  of  this  bone  gives  it  a  distinctive  character. 
It  is  placed  upon  the  trapezoides,  and  articulates  laterally  also 
with  the  trapezium,  and  the  magnum.  Its  carpal  or  upper  end 
presents,  in  the  middle,  a  deep  concavity  for  receiving  the  tra- 
pezoides, at  the  radial  side  of  which  is  a  small  plane  face  for 
articulating  with  the  trapezium,  and  at  the  ulnar  side  an  oblong 
surface,  the  upper  margin  of  which  joins  the  magnum,  and  the 
remainder  is  in  contact  with  the  third  metacarpal  bone.  The 
lower  end  presents  a  convex  head  extended  in  front  to  concur 
in  the  flexion  of  the  finger,  on  each  side  of  which  head  is  a 
concave  rough  surface  for  the  lateral  ligament.  The  poste- 
rior face  of  the  bone  presents  a  triangular  flat  surface,  the  base 
of  which  is  towards  the  finger  or  phalangial  end.  The  palmar 
face  is  concave,  longitudinally,  and  divided  by  a  middle  ridge, 
into  two  surfaces,  each  of  which  is  compressed  by  the  interos- 
seous  muscles.  A  tubercle  exists  on  the  back  of  the  bone  just 
below  its  carpal  end  for  the  insertion  of  the  tendon  of  the  ex- 
tensor  carpi  longior,  and  another  in  front  for  that  of  the  flexor 
radiali?. 

Of  the  Third  Metacarpal  Bone. — This  is  a  little  shorter  than 
the  last,  and  is  nearly  of  the  same  size,  but  its  carpal  extremity 
is  very  different.  The  latter  is  triangular,  and  is  bounded  on 
its  radial  side  by  a  sort  of  styloid  process,  with  a  tubercle  on 
the  posterior  face  of  it,  into  which  the  tendon  of  the  extensor 
radialis  brevior  is  inserted.  It  is  placed  upon  the  magnum,  to 
which  it  joins  by  a  slighlly  concave,  winding  surface.  It  also 
presents,  continuous  with  the  same  surface,  an  oblong  face 


THE  HAND.  199 

which  joins  the  second  metacarpal  bone,  and,  on  the  reversed 
side,  two  round  facets,  which  are  contiguous  to  the  fourth  me- 
tacarpal bone.  In  regard  to  its  lower  or  phalangial  extremity 
and  body,  this  bone  resembles  closely  the  one  last  described. 

Of  the  Fourth  Metacarpal  Bone.— This  bone  is  placed  upon 
the  unciforme,  and  has  a  very  small  articulating  surface  with 
the  magnum:  it  is  much  smaller  and  shorter  than  the  third 
metacarpal,  and  readily  distinguishable  by  these  circumstances. 
The  carpal  surface,  by  which  it  joins  the  unciforme,  is  trian- 
gular and  slightly  convex;  its  radial  edge  touches  the  magnum. 
Continuous  with  this  edge  are  two  small  faces,  slightly  convex, 
which  join  the  contiguous  faces  of  the  third  metacarpal  bone. 
On  the  reversed  side  of  the  fourth  metacarpal  is  an  oblong  face 
which  joins  the  carpal  end  of  the  fifth  metacarpal  bone.  In 
regard  to  its  body  and  phalangial  extremity,  this  bone  resem- 
bles the  two  preceding,  and  therefore  does  not  require  a  parti- 
cular description. 

Of  the  Fifth  Metacarpal  Bone. — It  is  placed  upon  the  unci- 
forme exterior  to  the  last,  and  is  both  smaller  and  shorter  than 
the  fourth.  The  carpal  extremity  presents  a  cylindroid  and 
slightly  convex  face,  for  articulating  with  the  unciforme,  at  the 
radial  margin  of  which  is  an  oblong  facet,  for  joining  the  fourth 
metacarpal:  just  below  the  outer  margin  is  a  small  tuberosity, 
into  which  is  inserted  the  tendon  of  the  extensor  ulnaris.  The 
lower  or  phalangial  extremity,  like  that  of  the  others,  presents 
a  convex  articular  face,  extended  in  front  for  the  flexion  of  the 
first  phalanx.  The  body  also  corresponds  with  that  of  the 
others,  excepting  that  it  is  more  flat  in  front. 


Of  the  Phalanges. 

The  fingers  are  named  numerically,  beginning  at  the  fore 
finger;  they  are  also  named  from  their  functions,  as  Indicator, 
Impudicus,  Annularis,  and  Auricularis. 

Each  finger  has  three  bones  in  it,  called  its  phalanges:  the 
bone  adjoining  the  metacarpus  is  the  first  phalanx,  the  middle 
bone  is  the  second,  and  the  other  the  third. 


200  SKELETON. 

The  first  phalanx  is  the  largest.  Its  posterior  face  is  semi- 
cylindrical,  the  anterior  face  is  flattened,  and  concave  in  its 
length.  The  two  surfaces  run  into  each  other  by  forming  a 
ridge  on  either  side,  from  which  arises  the  theca  of  the  flexor 
tendons.  The  metacarpal  extremity  is  enlarged,  and  presents 
a  superficial  cavity,  which  receives  the  end  of  the  metacarpal 
bone.  On  either  side  of  this  end  of  the  bone  is  a  small  tuber 
for  the  lateral  ligament.  The  lower  extremity  is  also  enlarged 
and  flattened  at  its  sides.  Its  articular  face  is  extended  in 
front,  and  presents  two  condyles,  or  small  heads,  for  joining 
the  second  phalanx. 

The  second  phalanx  is  likewise  second  in  size  and  length.  It 
is  semi-cylindrical  on  its  posterior  face,  flattened  on  its  ante- 
rior, which  is  somewhat  concave  in  its  length,  and  the  two  sur- 
faces form  a  ridge,  on  either  side,  into  which  the  tendon  of  the 
flexor  sublimis  is  inserted,  and  from  which  arises  the  theca  of 
the  flexor  tendons.  Its  extremities  are  slightly  enlarged :  the 
articular  face  of  the  upper  presents  two  superficial  cavities  for 
the  condyles  of  the  first  phalanx :  the  articular  face  of  the  lower 
extremity  presents  a  trochlea,  with  a  slight  elevation  at  each 
side. 

The  third  phalanx  is  the  smallest  of  the  three,  and  is  very 
different  from  the  others.  Its  superior  extremity  being  en- 
larged, presents  an  articular  face,  having  two  superficial  cavities, 
which  adjust  themselves  to  the  corresponding  face  of  the  last 
described  bone.  The  inferior  extremity  is  semicircular,  thin, 
and  flattened,  its  margin  being  very  rough,  and  somewhat  ex- 
panded. The  posterior  face  of  the  body  is  convex,  and  the  an- 
terior flat. 

The  phalanges  of  the  middle  finger  (Impudicus)  are  larger 
and  longer  than  the  others.  The  phalanges  of  the  fore  finger 
(Indicator)  are  next  in  size,  but  not  in  length,  as  the  ring  finger 
is  rather  longer  than  it.  The  phalanges  of  the  ring  finger  (An- 
nularis)  are  next  in  size,  and  those  of  the  little  finger  (Auricula- 
ris)  the  smallest  and  shortest  of  any. 

The  thumb  (Pollex)  having  but  two  phalanges,  the  first  cor- 
responds sufficiently  in  its  general  form  with  the  first  one  of 


DEVELOPMENT  OF  THE  UPPER  EXTREMITIES.  201 

the  fingers:  it  may  be  distinguished,  however,  by  its  shortness 
and  additional  size.  The  second  phalanx  of  the  thumb,  corre- 
sponding with  the  third  of  the  fingers,  is  only  to  be  distinguished 
by  its  additional  bulk  and  length. 

All  the  metacarpal  and  phalangial  bones  have  condensed  la- 
mellated  structure  externally,  and  a  cancellated  one  internally: 
and,  like  other  bones,  are  more  compact  in  their  bodies  than  at 
their  extremities. 

There  are  two  small  hemispherical  bones,  called  sesamoid, 
placed  upon  the  trochlea,  at  the  lower  extremity  of  the  meta- 
carpal bone  of  the  thumb.  They  answer  the  purposes  of  pa- 
tellss,  and  facilitate  the  action  of  the  short  flexor  muscle.  The 
metacarpal  bones  of  some  of  the  fingers  are,  in  robust  indivi- 
duals, occasionally  furnished  in  the  same  way. 


SECT.  V. OF  THE   DEVELOPMENT  OF  THE  UPPER  EXTREMITIES. 

At  birth  the  upper  extremities  are  larger  in  proportion  to  the 
lower  .than  they  are  at  any  subsequent  period  of  life,  owing, 
perhaps,  to  the  umbilical  arteries,  which  carry  off  to  the  placenta 
of  the  mother  the  greater  part  of  the  blood  which  afterwards 
goes  to  the  lower  extremities.  The  nearer  a  foetus  may  be  to 
the  embryo  state,  the  more  marked  is  this  relative  size  of  the 
extremities,  which  becomes  gradually  less  obvious  till  the  age 
of  puberty,  when'it  almost  entirely  disappears. 

At  birth,  the  ends  of  the  clavicles  are,  in  consequence  of  their 
advanced  ossification,  much  less  cartilaginous  than  those  of  the 
other  cylindrical  bones.  Its  shape,  also,  approaches  nearly  to 
that  of  the  adult  state. 

The  scapula  is  also  in  an  advanced  stage  of  ossification,  and 
large.  The  glenoid  cavity,  though  still  cartilaginous,  is  well 
sustained  by  a  bony  basement  coming  from  the  central  point  of 
ossification  of  the  scapula,  and  is  much  farther  ossified  than  the 
acetabulum.  The  acromion,  the  coracoid  process,  and  the  an- 
gles, are  still  cartilaginous. 

The  osjiumeri  is  cartilaginous  at  both  extremities,  which  are 
also  larger,  proportionally,  in  consequence  of  this  state.  Its 
inferior  extremity  is  remarkable  for  the  size  of  that  portion  of 
it  which  articulates  with  the  radius. 


202  SKELETON. 

In  the  fore  arm  the  extremities  of  its  bones  are  cartilaginous. 
The  ulna  has  the  olecranon  large,  while  its  coronoid  process  is' 
comparatively  small ;  the  greater  sigmoid  cavity  is,  consequent- 
ly, not  so  concave  as  in  the  adult.  The  position  of  the  radius, 
at  its  upper  end,  is  somewhat  peculiar,  for  it  is  much  more  an- 
terior than  in  the  adult;  a  circumstance  depending  upon  the 
greater  size  of  the  little  head  of  the  humerus,  upon  which  it 
rests.  This  arrangement  renders  pronation  more  extended  in 
the  fo3tus,  as  the  radius  always  crosses  the  ulna  with  additional 
facility.,  by  being  placed  more  anterior  to  it.  This  fact  is  strong- 
ly exemplified  in  the  bones  of  a  fore  extremity  of  animals.  Bi- 
chat  observes,  that  this  greater  extent  of  pronation  exposes  the 
annular  ligament  to  being  stretched  considerably  behind,  and, 
consequently,  the  radius  to  luxations  at  its  head ;  an  accident  by 
no  means  unfrequent  among  children.  The  late  Dr.  Physick 
says,  that  he  has  often  seen  it  in  consequence  of  nurses  incau- 
tiously seizing  them  by  the  fore  arm  to  help  them  over  gutters, 
or  to  render  them  other  assistance.  It  happens  while  the  arm 
is  in  a  state  of  pronation;  for  the  weight  of  the  body,  by  hang- 
ing from  it,  increases,  the  position  distends  the  ligaments,  and 
produces  luxation.  As  the  bones  of  the  fore  arm  in  the  foetus 
are  nearly  straight,  the  interosseal  space  decreases  gradually 
from  above  downwards. 

The  carpus  is  entirely  cartilaginous  at  birth,  and  consists  in 
the  same  number  of  pieces  that  it  does  in  the  adult.  Its  arti- 
cular cavities  are  well  formed.  Its  size  is  proportionate  to  what 
it  is  in  the  adult :  in  this  respect  it  differs  from  the  cartilaginous 
extremities  of  the  round  bones,  which  are  always  larger  from 
being  in  this  state.  The  carpus,  therefore,  appears  small  in  the 
foetus. 

The  metacarpus  is  cartilaginous  at  its  extremities,  but  ossified 
in  the  middle.  The  phalanges  are  in  the  same  state. 

SECT.  VI. OF  THE  MECHANISM  OF  THE  UPPER  EXTREMITIES. 

The  scapula  and  clavicle  are  for  the  superior  extremity  what 
the  os  innominatum  is  for  the  inferior;  in  consequence^f  which, 
some  anatomists  consider  them  as  .a  part  of  the  trunk  of  the 
body.  Though  the  convenience  of  anatomical  description  ge- 
nerally requires  them  to  be  associated  with  the  upper  extremi- 


MECHANISM  OF  THE  UPPER  EXTREMITIES.  203 

ty,  I  shall  depart  from  the  rule  on  the  present  occasion,  and 
view  them  only  as  the  basis  of  the  attachments  and  motions  of 
the  os  humeri,  and  of  the  remaining  parts  of  the  superior  ex- 
tremity. 

The  upper  extremities,  considering  them  as  commencing  with 
the  os  humeri,  differ  materially  in  their  position  from  the 
lower.  They  are  placed  much  farther  behind ;  of  which  one 
may  be  satisfied  fully  by  drawing  a  line  from  the  middle  of  the 
glenoid  cavity,  to  the  middle  of  the  acetabulum  of  the  same 
side;  the  body  being  perfectly  erect  at  the  time,  the  line  will 
be  found  oblique.  The  advantage  of  this  arrangement  is  to 
give  greater  latitude  of  motion  to  the  upper  extremity  than  if 
it  had  been  placed  more  in  front.  Another  important  benefit 
is,  that  by  the  bulk  of  the  shoulder  being  placed  behind  the 
centre  of  gravity,  the  erect  position  is  more  easily  preserved ; 
a  different  position  of  it,  by  throwing  its  weight  forwards,  would 
have  had  a  continually  tendency  to  produce  falls,  and  to  effect 
somewhat,  in  man,  the  same  inconvenience  which  is  felt  by  the 
quadruped  in  the  erect  position.  Another  point,  also  of  some 
interest  in  the  position  of  the  upper  extremities,  is  the  distance 
to  which  they  are  separated  from  each  other  by  the  lateral  pro- 
jection of  the  scapulae,  and,  consequently,  of  the  glenoid  cavi- 
ties. A  distance  owing  to  the  length  of  the  clavicles,  and  which 
considerably  exceeds  the  distance  between  the  heads  of  the  ossa 
femorum. 

When  the  whole  length  of  the  superior  is  compared  with  that 
of  the  inferior  extremities,  the  difference  is  not  so  great  as  one 
may  suppose.  The  former  is  ascertained  by  a  line  drawn  from 
the  head  of  the  os  humeri  to  the  end  of  the  middle  finger :  as  the 
hand  is  parallel  with  the  bones  of  the  fore  arm,  its  length  is  also 
included,  which  amounts  to  a  considerable  portion  of  the  whole. 
On  the  contrary,  from  the  foot  being  articulated  at  right  angles 
with  the  leg,  only  its  thickness  contributes  to  the  length  of  the 
lower  extremity.  As  far,  however,  as  individual  bones  are  con- 
cerned, those  of  the  upper  extremity,  with  the  exception  of  its 
phalanges,  are  uniformly  shorter  than  the  corresponding  bones 
of  the  lower  extremity.  The  os  humeri  is  much  shorter  than 
the  os  femoris — the  bones  of  the  fore  arm  than  the  bones  of  the 
leg — the  carpal  and  metacarpal  bones  than  the  tarsal  and  me- 
tatarsal. 


204  SKELETON. 

The  bones  of  the  upper  extremity  are  much  less  robust  than 
those  of  the  lower,  a  very  certain  indication  of  the  difference  of 
the  uses  for  which  they  were  intended.  Their  articular  surfaces 
are  arranged  for  great  variety  and  extent  of  motion,  in  the 
seizing  and  handling  of  bodies;  whereas  in  the  lower  extremity, 
they  are  fashioned  so  as  to  suit  the  comparatively  limited  num- 
ber of  motions  requisite  to  progression,  and  to  sustain  the  body 
firmly  in  the  upright  position.  The  carpus  and  metacarpus  are 
much  smaller  than  the  tarsus  and  the  metatarsus,  because  the 
latter  are  intended  to  support  a  great  weight.  On  the  contrary, 
the  phalanges  of  the  fingers  are  much  better  developed  than  the 
phalanges  of  the  toes,  because  the  latter  are  not  destined  to  hold 
bodies  and  to  examine  them,  and  may  be  dispensed  with  both 
in  standing  and  in  progression. 

The  motions  of  the  upper  extremity  are  immensely  varied, 
and  by  a  short  attention  to  them,  some  useful  hints  may  be  ob- 
tained in  regard  to  dislocations. 


SECT.  VII. OF  THE  MOTIONS  OF  THE  SHOULDER. 

The  clavicle  performs  a  very  important  office  in  the  actions 
of  the  shoulder,  by  preserving  it  in  a  fit  attitude  for  the  motions 
of  the  upper  extremity.  The  simple  movements  of  the  clavicle, 
of  which  the  sterno-clavicular  articulation  is  the  centre,  are 
those  of  elevation,  depression,  advancing,  and  retreating,  and  a 
rapid  succession  of  these  produces  circumduction.  The  weight 
of  the  shoulder  is  also  sustained  by  the  clavicle,  by  the  latter 
being  fastened  at  the  extremity  next  to  the  sternum,  and  having 
in  the  cartilage  of  the  first  rib  a  fulcrum,  intermediate  to  this 
attachment  and  to  the  weight  at  its  other  end.  This  is  proved 
conclusively  by  its  fracture;  for  in  that  case  the  shoulder  inva- 
riably falls  down,  from  the  lever  being  broken  which  kept 
it  up. 

The  clavicle,  also,  by  keeping  the  glenoid  cavity  at  a  dis- 
tance from  the  side  of  the  thorax,  and  directed  outwards,  gives 
great  facility  and  latitude  to  certain  motions  in  the  human  sub- 
ject; and  which  are  performed  with  difficulty,  and  very  imper- 
fectly, in  animals  not  having  a  clavicle.  A  principal  one  of 
these  motions  is  circumduction,  manifested  by  the  elbow  being 


MOTIONS  OF  THE  SHOULDER  JOINT.  205 

turned  inwards  or  outwards,  and  in  most  persons  extends  to 
three-fourths  or  even  an  entire  circle.  This  motion  concurs  in 
the  action  which  brings  the  hand  to  the  mouth,  in  consequence 
of  which  such  an  action  is  performed  with  difficulty  when  the 
clavicle  is  broken.  After  an  accident  of  the  kind,  the  head,  in- 
stead of  remaining  stationary  as  usual,  is  advanced  towards  the 
hand,  without  which  the  act  cannot  be  accomplished.  A  cer- 
tain length  in  the  clavicle  seems  indispensable  to  the  vigorous 
and  perfect  action  of  the  shoulder  in  particular  movements;  if 
the  clavicle  be  disproportionately  long,  as  in  females,  these 
movements  are  executed  with  inevitable  awkwardness  and  im- 
becility; as,  for  example,  in  throwing  a  stone. 

The  scapula  presents  a  moveable  basis,  on  which  the  mo- 
tions of  the  arm  are  accomplished.  Its  primary  motions  are 
such  as  have  been  assigned  to  the  clavicle,  in  consequence  of 
the  connexion  between  these  bones;  besides  which,  in  all  the 
extreme  motions  of  the  humerus,  backwards  or  forwards,  the 
scapula  is  caused  to  perform  a  partial  rotation,  the  axis  of 
which  is  indicated  by  a  line  drawn  from  the  end  of  the  acro- 
mion  to  the  inferior  angle.  When  the  arm  is  brought  very  far 
forwards,  the  inferior  angle  of  the  scapula  is  carried  outwards, 
and  somewhat  elevated,  while  the  superior  angle  is  directed 
towards  the  spine,  and  somewhat  depressed.  But,  when  the 
arm  is  carried  very  far  backwards,  the  inferior  angle  is  direct- 
ed towards  the  spine,  and  the  superior  angle  looks  forwards 
and  upwards.  The  clavicle  in  these  cases  moves  inconsidera- 
bly, as  the  scapula  enjoys  a  pendulous  motion,  and  its  point  of 
suspension  is  the  outer  end  of  the  clavicle;  at  which  place  the 
oblong  articular  surfaces  slide  laterally  upon  each  other  and 
decussate.  The  extreme  degrees  of  these  motions  tend  to  dis- 
locate this  articulation,  but  the  accident  is  prevented  by  the 
strong  coraco-clavicular  ligament,  which,  by  its  peculiar  posi- 
tion and  conformation,  resists  firmly  at  a  certain  point.  In  the 
abduction  and  adduction  of  the  arm  the  scapula  is  motionless. 

SECT.  VIII. OF  THE  MOTIONS  OF  THE  SHOULDER  JOINT. 

The  os  humeri  is  susceptible  of  elevation,  depression,  ad- 
vancing, retreating,  circumduction,  and  rotation. 
VOL   I.— 18 


206  SKELETON. 

In  elevation,  the  head  of  the  os  humeri  slides  downwards  in 
the  glenoid  cavity,  and  distends  the  lower  part  of  the  capsular 
ligament.  In  this  motion  the  scapula  is  apt  to  follow  it ;  in 
which  case  there  will  be  a  less  degree  of  distention  in  the  cap- 
sular ligament.  If  the  os  humeri  be  carried  forwards,  its  ele- 
vation is  performed  with  much  more  ease,  from  the  readiness 
with  which  the  scapula  follows  it;  but  if  it  be  carried  backwards, 
this  facility  is  much  diminished.  It  is  in  the  latter  position, 
therefore,  that  dislocations  downwards  are  most  disposed  to  oc- 
cur when  violence  is  offered  to  the  joint.  If  in  every  case  the 
scapula  could  follow  the  motions  of  the  os  humeri,  so  as  to  pre- 
sent fairly  its  glenoid  cavity,  luxations  would  be  comparatively 
rare;  but  generally  the  violence  offered  transmits  its  momentum 
so  speedily  to  the  joint,  that  the  muscles  of  the  scapula  are 
taken  by  surprise,  and  have  not  time  to  adjust  properly  the  gle- 
noid cavity. 

In  the  depression  of  the  os  humeri,  the  parts  constituting  the 
shoulder  joint  are  in  their  most  natural  and  easy  position.  The 
capsular  ligament  becomes  very  loose  below,  and  is  somewhat 
stretched  above.  Any  degree  of  force  which  might  be.  applied 
to  the  member,  is  warded  off  and  its  direction  changed  by  the 
intervention  of  the  trunk  of  the  body.  Should,  however,  the 
force  be  applied  directly  in  the  axis  of  the  bone*,  the  projection 
of  the  aeromion  process,  and  the  strength  of  the  triangular  liga- 
ment of  the  scapula,  would  arrest  the  dislocation. 

When  the  os  humeri  is  advanced,  the  posterior  part  of  the 
eapsular  ligament  is  put  upon  the  stretch;  but  the  form  and  ar- 
rangement of  the  articular  surfaces  are  somewhat  favourable  to 
this  position,  and  accordingly  it  is  one  of  but  little  inconve- 
nience. When  the  os  humeri  is  retracted,  its  head,  by  being 
directed  forwards,  exercises  considerable  force  upon  the  fore 
part  of  the'  capsular  ligament,  and  when  assisted  by  an  exter- 
nal momentum  is  disposed  to  dislocation,  forwards  and  in- 
wards. 

The  motion  of  circumduction  is  very  extensive  in  the  shoul- 
der joint;  and  by  it  the  os  humeri  describes  a  cone,  of  which 
the  glenoid  cavity  is  the  apex.  It  is  a  regular  succession  of 
the  movements  already  mentioned,  and  in  consequence  of  all 
the  motions  forwards  of  the  os  humeri  being  more  easy  and 


MOTIONS  OF  THE  FORE  ARM.  207 

natural,  the  axis  of  the  cone,  instead  of  being  directly  outwards, 
is  somewhat  forwards. 

By  rotation,  is  meant  the  revolving  of  the  os  humeri  upon 
itself.  The  centre  of  this  movement  is  not  the  axis  of  the  bone5 
but  is  removed  to  one  side  of  it,  by  the  lateral  projection  of  the 
head.  The  neck,  however,  is  too  short  and  thick  to  permit 
any  great  extent  to  this  motion;  it,  accordingly,  is  limited  in 
such  a  way  as  never  to  amount  to  luxation.  Its  greatest  ex- 
tent, in  most  persons,  does  not  exceed  the  describing  of  half  a 
circle,  which  may  be  ascertained  by  applying  a  finger  upon 
the  internal  condyle  of  the  os  humeri.  By  it  the  capsular  liga- 
ment is  rendered,  alternately,  loose  and  tense  on  its  front  and 
back  parts.  Bichat  observes,  that  in  the  anchylosis  of  the 
elbow  joint,  this  motion,  by  habit,  is  much  augmented,  so  as  to 
supply  the  want  of  rotation  of  the  head  of  the  radius  upon  the 
ulna.  The  scapula  and  the  clavicle  do  not  vary  their  position 
in  rotation. 


SECT.  IX. OF  THE  MOTIONS  OF  THE  FORE  ARM. 

There  are  two  kinds  of  motion  in  the  fore  arm.  In  the  one, 
the  fore  arm  is  flexed,  or  extended  upon  the  arm,  and  in  the 
other,  the  radius  only  changes  its  position  in  regard  to  the 
ulna. 

1.  The  ulna  is  the  essential  agent  of  the  first,  in  consequence 
of  its  manner  of  articulation  with  the  os  humeri ;  the  radius  is 
only  accessory,  and  is  drawn  by  the  ulna  into  a  participation  in 
its  motions.  These  two  bones,  it  will  be  recollected,  are  dis- 
posed of  in  an  inverse  manner,  the  larger  part  of  the  ulna  being 
above,  while  the  larger  part  of  the  radius  is  below.  This  ar- 
rangement causes  the  ulna  to  present  the  principal  articular 
surface  for  union  with  the  os  humeri,  while  the  radius  affords 
the  principal  surface  to  the  carpus;  it  also  gives  to  the  whole 
fore  arm  a  great  uniformity  in  its  transverse  diameter.  The 
fore  arm  executes,  upon  the  arm,  flexion,  extension,  and  lateral 
inclination. 

Where  the  flexion  is  complete,  the  coronoid  process  is  re- 
ceived into  its  cavity,  on  the  front  of  the  os  humeri;  and  the  ole- 


208  SKELETON. 

cranon,  having  left  its  cavity,  is  placed  below  the  condyles. 
In  this  state  the  capsular  ligament  is  stretched  at  its  posterior 
part,  while  the  anterior  is  thrown  into  folds,  and  is  relaxed 
along  with  the  lateral  ligaments.  In  the  demi-flexion  of  the 
arm,  there  is  a  more  equal  degree  of  tension  of  the  several  li- 
gaments. When  the  os  humeri  is  reposing  in  its  most  easy  at- 
titude, at  the  side  of  the  body,  if  the  fore  arm  be  flexed,  its  line 
of  motion  directs  the  hand  towards  the  mouth;  a  circumstance 
which  is  accounted  for  by  the  peculiar  obliquity  of  the  troch- 
lea,  on  the  lower  part  of  the  os  humeri,  upon  which  the  ulna 
revolves,  and  is  independent  of  any  special  act  of  volition.  It 
is  said  that  man,  above  all  other  animals,  has  the  mechanism 
of  the  upper  extremity  most  particularly  addressed  to  the  latter 
motion,  to  the  perfection  of  which  the  clavicle  is  indispensable. 
It  is  in  consequence  of  this  application  of  the  clavicle,  that  if  it 
be  broken,  man,  like  animals  which  are  entirely  deprived  of  it, 
will,  in  the  flexions  of  the  fore  arm,  more  easily  carry  the  hand 
to  the  opposite  shoulder  than  to  the  mouth. 

In.  the  full  extension  of  the  fore  arm,  the  olecranon  process 
being  received  into  its  cavity,  is  much  above  the  condyles  of 
the  os  humeri.  The  lateral  ligaments,  as  well  as  that  part  of 
the  capsule  on  the  front  of  the  joint,  are  in  a  state  of  tension. 
When  the  extremity  is  in  this  position,  a  fall  upon  the  hand 
may  produce  a  dislocation  backwards.  In  this  case  the  fore 
arm  being  fixed,  the  coronoid  process  affords  the  surface  upon 
which  the  principal  momentum  of  the  fall  is  felt.  If  the  liga- 
ments on  the  front  of  the  joint  be  not  strong  enough  to  with- 
stand the  force,  they  are  lacerated,  and  the  articular  surfaces, 
passing  each  other,  the  upper  parts  of  the  ulna  and  radius  are 
driven  behind  the  os  humeri.  Bichat  asserts,  that  nothing  is 
more  easy  than  to  produce  such  a  luxation  on  the  dead  body  by 
a  similar  proceeding,  and  that  he  has  repeatedly  done  it — that 
it  is  about  as  easy  to  produce  this  dislocation,  as  it  is  difficult  to 
effect  one  at  the  scapulo-humeral  articulation.  In  a  moderate 
extension  of  the  fore  arm,  produced  by  a  small  weight  suspend- 
ed on  the  hand  at  arm's  length,  there  is  a  well  marked  pressure 
of  the  inferior  extremity  of  the  os  humeri  against  the  ligaments 
in  front  of  the  articulation,  which  is  augmented  by  a  tendency 
of  the  ulna  to  describe  the  arc  of  a  circle,  from  above  down- 
wards, and  to  separate  itself  from  the  os  humeri.  In  this  case 


MOTIONS  OF  THE  FORE  ARM.  209 

the  muscles  which  flex  the  fore  arm  are  kept  so  much  in  the 
line  in  which  they  contract,  or  are  so  little  removed  from  the 
axis  of  their  own  motion,  that  they  contribute  but  little  to  sus- 
tain the  fore  arm  in  situ;  the  weight  is,  therefore,  actually  sus- 
tained  by  the  ligaments  in  front  of  the  articulation.  But  they 
being  pressed  and  drawn  in  the  manner  mentioned,  such  great 
pain  and  weariness  are  produced  as  to  render  a  continued  sus- 
pension of  the  weight  insupportable,  the  experimenter  is,  there- 
fore, in  a  short  time,  under  the  necessity  either  of  casting  off 
the  weight  or  of  giving  such  a  degree  of  flexion  to  the  fore  arm 
as  will  allow  the  muscles  to  contract  more  advantageously. 

Besides  flexion  and  extension,  the  ulna  has  a  sort  of  rocking 
motion  when  the  fore  arm  is  only  half  bent;  but  when  the  lat- 
ter is  at  either  extreme  of  the  former  positions,  this  motion  is 
imperceptible,  owing  to  the  nature  of  the  articular  surfaces  and 
the  resistance  of  the  ligaments. 

2.  In  the  rotations  of  the  radius  upon  the  ulna,  the  latter  is 
almost  motionless,  excepting  the  case  specified  in  the  last  para^ 
graph.  The  position  of  the  radius  on  a  plane  somewhat  ante- 
rior to  the  ulna,  its  small  cylindrical  upper  extremity,  and  its 
broad  lower  one,  all  concur  in  facilitating  rotations  forwards 
and  backwards.  It  is  owing  to  the  hand  following  these  mo- 
tions that  the  first  is  expressed  by  the  term  pronation,  in  which 
the  palm  of  the  hand  is  directed  downwards ;  and  the  second, 
supination,  in  which  the  palm  is  upwards  and  the  back  of  the 
hand  downwards. 

Pronation  is  the  most  common,  and,  consequently,  the  easiest 
position  to  the  fore  arm,  when  not  carried  to  an  extreme:  it  is 
adopted  involuntarily,  simply  by  the  action  of  the  ligaments  and 
the  particular  shape  of  the  articulating  surfaces  of  the  bones. 
It  is  the  posture  most  generally  suited  to  the  examination  and 
grasping  of  surrounding  bodies.  In  order  that  it  may  be  ac- 
complished fully,  the  superior  extremity  of  the  radius  rolls  on 
its  own  axis,  in  the  loop  formed  by  the  annular  ligament  and 
the  lesser  sigmoid  cavity  of  the  ulna;  while  the  lower  extremi- 
ty revolves  around  the  little  head  of  the  ulna  below.  The  mid- 
dle part  of  the  radius  crosses  that  of  the  ulna,  and  the  interos- 
seous  space  is  diminished.  An  excess  of  this  motion  will  pro* 
duce  luxation  either  above  or  below,  but  more  easily  at  tha 

18* 


210  SKELETON. 

latter  place ;  both  on  account  of  the  greater  extent  of  motion 
there,  and  of  the  comparative  weakness  of  the  ligaments. 

In  supination,  a  movement  the  reverse  of  what  is  described, 
takes  place ;  the  radius  revolves  outwardly,  and  is  brought  pa- 
rallel with  the  ulna.  If  by  any  force  it  be  carried  beyond  this 
line,  a  dislocation  may  occur,  in  which  the  little  head  of  the 
ulna,  abandoning  the  sigmoid  cavity  of  the  radius,  will  be  thrown 
in  front  of  it.  An  accident,  however,  said  to  be  very  unusual. 

Bichat  considers  the  cartilage  between  the  ulna  and  the  cu- 
neiforme  as  a  principal  obstacle  to  these  luxations;  but  when  it 
is  insulated  or  separated  from  the  cartilage  of  the  radius,  as 
sometimes  occurs,  the  joint  is  very  much  weakened  thereby, 
and  more  exposed  to  dislocations. 


SECT.  X.  —  OF  THE  MOTIONS  OF  THE  HAND. 

The  hand,  as  a  whole,  performs  upon  the  forearm,  flexion, 
extension,  lateral  inclination,  and  circumduction.  As  it  only 
follows  the  motion  of  the  radius  in  pronation  and  supination, 
and  does  not  contribute  in  the  slightest  degree  to  either,  its  ap- 
propriate motions  can  all  be  performed  independently  of  them. 

In  flexion  the  convex  head,  formed  by  the  first  range  of  car- 
pal bones,  slides  from  before  backwards  in  the  concavity  which 
receives  it.  The  posterior  part  of  the  capsufor  ligament  is 
stretched,  and  the  anterior  thrown  into  folds,  while  the  lateral 
ligaments  remain  at  their  ease.  In  extension,  with  the  excep- 
tion of  the  lateral  ligaments,  the  phenomena  are  reversed.  This 
extension,  as  is  well  known,  not  only  brings  the  hand  into  the 
same  line  with  the  bones  of  the  fore  arm,  but  carries  it  beyond 
that  line  till  it  forms  almost  a  right  angle  with  it.  The  wrist 
joint,  in  this  respect,  differs  from  the  other  ginglymous  articu- 
lations; but  what  it  gains  in  extension  it  loses  in  flexion,  as  it 
cannot  be  bent  so  much  as  either  the  elbow  or  knee.  The  ar- 
rangement, however,  gives  great  facility  to  the  use  of  the  hand. 

In  the  lateral  inclinations  of  the  hand,  the  capsule  in  front  of 
and  behind  the  wrist,  is  but  little  affected,  but  the  lateral  liga- 
ments are  alternately  relaxed  and  lightened.  As  the  articular 
surfaces  are  extensive  in  the  line  of  these  motions,  dislocations 
in  the  direction  of  either  of  them  are  very  uncommon,  and 
when  they  do  occur  they  are  for  the  most  part  incomplete. 


MOTIONS  OF  THE  HAND.  211 

Circumduction  is  produced  by  a  regular  succession  of  the 
motions  described;  it,  therefore,  does  not  require  a  specific  no- 
tice. 

Of  the  Partial  Motions  of  the  Hand.-~We\\  marked  changes 
of  position  occur  between  the  first  and  second  rows  of  the  car- 
pus: these  are  principally  flexion  and  extension.  Lateral  in- 
clination or  abduction  and  adduction  are  extremely  limited,  and 
circumduction  does  not  exist.  The  motions,  such  as  they  are, 
are  confined  within  much  narrower  limits  than  those  of  the  ra- 
dio-carpal articulation,  and  have  for  their  main  fulcrum  the 
head  of  the  magnum. 

The  lateral  articular  surfaces  of  the  several  bones  of  the  car- 
pus, though  they  present  the  arrangement  of  joints,  have  not  an 
appreciable  motion  upon  each  other.  Whatever  changes  of  po- 
sition happen  among  them,  are  probably  so  obscure  that  they 
never  appear,  except  under  the  influence  of  great  and  sudden 
violence.  The  complexity  of  the  mechanism  of  the  wrist, 
seems  to  have  a  double  object  in  view :  for  ordinary  circum- 
stances of  impulse  and  motion,  the  flexion  and  extension  of  the 
first  row  upon  the  second,  as  a  whole,  is  sufficient;  but  when  a 
great  momentum  is  communicated  to  the  structure,  the  number 
of  pieces  which  form  it,  and  the  variety  of  their  shapes  and  mode 
of  attachment,  diffuse  the  violence  throughout  the  whole  wrist, 
and  generaHy  save  it  from  dislocation  or  fracture.  The  fracture 
of  a  single  bone,  excepting  from  gun-shot  wounds,  is  a  very  un- 
usual circumstance:  I  have,  however,  in  possession  a  scaphoides 
which  was  broken  through  transversely,  and  had  probably  been 
in  that  state  for  a  long  time;  as  all  appearance  of  inflammation, 
at  the  period  of  my  finding  it,  was  absent,  and  as  the  fractured 
surfaces  had  become  highly  polished  by  rubbing  against  one  an- 
other. 

-The  pisiform  bone  moves  with  much  freedom  inwardly  and 
outwardly  on  the  cuneiform,  but  its  motion  up  and  down  is  re- 
sisted by  the  muscles  which  are  attached  to  it.  Owing  to  its 
articular  cavity  being  insulated,  and  to  its  own  remoteness,  a 
dislocation  of  it,  if  it  did  occur,  would  interfere  but  little  with 
the  general  uses  of  the  hand. 

The  metacarpal  bone  of  the  thumb  has  a  very  free  motion  on 


SKELETON. 

the  trapezium,  in  flexion,  extension,  adduction,  abduction:  and 
circumduction  is  the  result  of  the  other  four.  In  consequence 
of  this  variety  of  movement  in  it,  of  its  position  on  a  plane  an- 
terior to  that  of  the  fingers,  and  of  a  corresponding  obliquity 
of  the  trapezium,  the  thumb  can,  in  all  cases  of  grasping  and 
examining  bodies,  antagonize  the  fingers.  The  circumduction 
of  the  thumb  resembles  very  much  that  of  the  wrist,  or  shoul- 
der joint,  though  the  mechanism  of  the  articular  surfaces  is  dif- 
ferent. In  this  motion,  it  describes  a  cone  or  circle,  the  ante- 
rior segment  of  which  is  larger,  and  performed  with  more  fa- 
cility than  the  posterior. 

The  second  and  third  metacarpal  bones  are  so  closely  bound 
to  the  carpus,  that  their  motion  above  is  almost  imperceptible; 
in  consequence  of  their  length,  the  motion  is  more  appreciable 
below,  but  even  there  it  is  very  much  restricted.  The  fourth 
metacarpal  bone  has  a  limited  ginglymous  movement,  which  is 
sufficiently  demonstrable,  and  the  fifth  has  it  in  a  considerable 
degree;  it  also  admits  of  a  sort  of  adduction,  by  which  it  is 
brought  nearer  to  the  other  bone. 

The  first  phalanges  admit  of  flexion,  extension,  adduction,  ab- 
duction; and  circumduction,  by  the  successive  performance  of 
the  others.  The  first  phalanx  of  the  thumb  has  the  three  last 
motions  very  much  curtailed,  in  consequence  of  the  necessity 
of  great  strength  and  stability  in  this  joint,  so  as  to  antagonize 
firmly  the  fingers.  The  remaining  phalanges  perform,  simply, 
flexion  and  extension.  The  latter,  as  in  the  knee  and  elbow, 
rarely  goes  beyond  the  axis  of  the  limb,  whereas  the  former, 
from  the  extent  of  the  articular  surfaces  and  the  particular  me- 
chanism of  the  joint,  permits  the  hand  to  be  closed  and  dou- 
bled. 

From  what  has  been  said,  it  will  not  be  difficult  to  form  $ 
general  conception  of  the  great  variety  of  motions  resulting 
from  the  number  and  arrangement  of  the  pieces  constituting 
the  upper  extremity.  The  os  humeri  being  the  basis  of  them, 
may  be  presented  in  any  direction;  the  bones  of  the  fore  arm 
may  be  alternately  retracted  or  protruded,  and  by  the  revolving 
of  the  radius,  will  permit  the  palm  of  the  hand  to  apply  itself  at 


THIGH  BONE.  213 

any  point ;  and,  again,  the  multiplicity  of  simple  motions  of  the 
hand,  and  the  exhaustless  variety  of  their  compounds,  contri- 
bute to  give  to  the  upper  extremity,  in  man,  a  perfection  of  me- 
chanism infinitely  beyond  any  thing  which  can  be  devised  by 
the  powers  of  art:  a  sentiment  cogently  expressed  by  the  late 
Professor  Wistar:  who  remarked,  that  "  The  human  hand,  di- 
rected by  the  human  mind,  is  the  most  perfect  instrument  that 
man  ever  saw  or  ever  will  see." 


CHAPTER  VI. 

OF  THE  INFERIOR  EXTREMITIES. 

THE  bones  of  the  inferior  extremities  are  the  os  femoris,  the 
tibia,  fibula,  patella,  and  a  large  number  which  enter  into  the 
composition  of  the  foot. 

SECT.  i. — OF  THE  THIGH  BONE, — (Os  Femoris,  Femur.) 

This  is  the  only  bone  in  the  thigh,  and  extends  from  the  trunk 
to  the  leg.  It  is  considerably  the  longest  and  largest  bone  in  the 
skeleton,  and  presents  a  conformation  entirely  peculiar.  For 
the  purposes  of  description,  it  is  divided  into  the  two  extremities 
and  the  body. 

The  superior  or  iliac  extremity  presents  three  well  marked 
eminences,  the  head,  the  great  and  the  little  trochanter.  The 
head  is  the  articular  surface  above,  and  forms  rather  more  than 
one-half  of  a  perfect  sphere.  Its  smoothness  indicates  the  exist- 
ence of  a  cartilaginous  crust  on  it  during  life,  and  is  only  inter- 
rupted by  a  small  pit  a  little  below  its  centre,  which  gives  at- 
tachment to  the  round  ligament  of  the  hip  joint.  Its  articular 
surface  is?more  extensive  above  than  below,  as  that  part  is  chief- 
ly employed  in  sustaining  the  trunk,  and  comes  in  contact  with 
a  corresponding  surface  of  the  os  innominatum.  The  head  is  sup- 
ported on  a  branch  of  the  os  femoris  called  the  neck,  which,  pro- 


214  SKELETON. 

jecting  from  the  internal  face  of  the  bone  between  the  trochan- 
ters,  is  directed  inwards  and  upwards  at  an  angle  of  about  thirty- 
five  degrees,  but  varying  in  different  subjects.  The  neck  is  two 
inches  in  length,  oval,  or  resembling  a  flattened  cylinder,  the 
greater  diameter  of  which  is  vertical ;  and  arises  by  an  exten- 
sive base  along  the  upper  end  of  the  os  femoris.  It  has  a  great 
multitude  of  foramina  dispersed  over  it,  which  penetrate  to  its 
interior,  and  give  passage  to  blood  vessels;  the  largest  of  them 
are  on  its  posterior  surface.  Some  of  these  foramina  are  also 
occupied  by  fibres.  A  superficial  horizontal  fossa,  formed  by 
the  tendon  of  the  obturator  externus,  may  be  seen  crossing  the 
posterior  face  of  the  base  of  the  neck. 

The  great  trochanter  is  situated  at  the  superior  part  of  the 
base  of  the  neck,  and  though  presenting  a  well  marked,  elevated 
summit,  rising  straight  upwards,  does  not  reach  the  altitude  of 
the  head,  but  falls  short  of  it  half  an  inch.  The  trochanter 
major  rests  upon  a  broad  base,  has  its  surface  much  diversified, 
is  somewhat  prominent  in  front  and  externally;  but  presents  on 
the  side  which  is  next  to  the  head  of  the  bone  a  deep  rough  con- 
cavity, which  is  occupied  by  the  insertion  of  the  small  rotatory 
muscles  on  the  back  of  the  pelvis.  On  its  summit  is  a  small 
smooth  spot,  marked  by  the  insertion  of  the  pyriformis  muscle; 
below  this,  and  also  externally,  is  a  broad  surface,  slightly  con- 
vex, into  which  the  gluteus  medius  is  inserted;  below  this,  again, 
is  a  second  prominent  and  rounded  surface,  over  which  a  part 
of  the  tendon  of  the  gluteus  magnus  plays.  On  the  front  of 
the  trochanter,  and  just  in  advance  of  the  insertion  of  the  glu- 
teus medius,  is  an  oblong  surface,  proceeding  obliquely  down- 
wards and  outwards,  into  which  is  inserted  the  gluteus  mini- 
mus. 

The  trochanter  minor  is  much  smaller  than  the  other,  and  is 
a  conical  process,  placed  on  the  internal  posterior  face  of  the 
bone,  at  the  lower  end  of  the  root  of  the  neck.  It  receives  the 
common  tendon  of  the  iliacus  internus  and  psoas  magnus  mus- 
cles. A  broad  elevated  ridge  joins  the  two  trochanters  on  the 
posterior  face  of  the  bone,  and  from  its  middle  half  arises  the 
quadratus  femoris  muscle.  A  much  smaller  ridge,  and  by  no 


THIGH  BONE.  215 

means  so  elevated,  runs  in  front,  from  the  one  process  to  the 
other,  and  indicates  the  line  of  attachment  of  the  capsular  liga- 
ment of  the  hip  joint. 

The  inferior  extremity  of  the  os  femoris  is  much  more  volu- 
minous than  the  superior,  and  is  divided  into  two  parts,  called 
the  internal  and  the  external  condyle.  These  condyles  are  of 
very  nearly  the  same  size,  but,  being  separated  by  a  notch  be- 
hind, they  are  placed  somewhat  obliquely  in  regard  to  each 
other;  and  the  internal,  from  being  the  most  oblique,  and,  con- 
sequently, the  most  protuberant,  also  seems  to  be  the  larger. 
If  the  os  femoris  be  placed  exactly  vertical,  the  internal  con- 
dyle has  the  appearance  of  being  the  longest;  but,  if  it  be  placed 
in  its  natural  obliquity,  the  lower  face  of  the  condyles  is  on  the 
same  plane.  In  front,  the  condyles  unite  to  form  an  articular 
trochlea,  on  which  the  patella  plays :  this  trochlea  is  unequally  di- 
vided by  a  vertical  depression,  so  as  to  have  its  more  extensive 
surface  externally.  This  latter  surface  is  the  anterior  part  of 
the  external  condyle,  and  is  much  more  elevated  than  the  in- 
ternal part  of  the  trochlea,  which  belongs  to  the  internal  con- 
dyle. Posteriorly,  the  internal  condyle  projects  more  than  the 
external,  and  both  have  the  articular  surfaces,  there,  so  much 
elongated  backwards  and  upwards,  as  to  admit  of  a  very  great 
flexion  of  the  leg. 

Each  condyle  presents  an  internal  and  an  external  face.  The 
internal  condyle  has  on  its  internal  face  a  tuberosity,  from  which 
proceeds  the  internal  lateral  ligament  of  the  knee;  on  its  exter- 
nal face  it  forms  one-half  of  the  notch  which  separates  it  from 
the  other  condyle,  and  at  its  anterior  part  in  the  notch  may  be 
observed  a  small  depression,  from  which  proceeds  the  poste- 
rior crucial  ligament.  The  external  condyle,  also,  has  on  its 
external  face  a  tuberosity,  from  which  proceeds  the  external 
lateral  ligament  of  the  knee,  and  just  below  it  a  depression  for 
the  origin  of  the  popliteus  muscle.  Its  internal  face  forms  the 
other  half  of  the  notch  just  mentioned,  and  on  the  posterior  part 
of  this  face  is  a  small  depression  for  the  attachment  of  the  an- 
terior crucial  ligament.  The  inferior  face  of  the  condyles  is 
somewhat  flattened,  the  transverse  diameter  of  that  of  the  ex- 
ternal being  rather  longer  than  the  other.  The  inferior  extre- 


216  SKELETON. 

mity  of  the  os  femoris  is  beset  with  foramina,  large  and  small, 
for  the  passage  of  vessels  and  the  attachment  of  fibres. 

The  body  of  the  os  femoris  begins  at  the  trochanters,  and 
terminates  in  the  condyles.  It  is  slightly  bent,  so  as  to  present 
the  convexity  of  the  curve  forwards.  Its  size  is  gradually  di- 
minished to  the  middle;  it  then  begins  to  enlarge,  and  continues 
to  augment  till  it  terminates  in  the  large  inferior  extremity. 
The  body  is  very  nearly  round,  and  departs  from  that  figure 
only  on  its  posterior  face,  where  an  elevated  rough  ridge  is 
found,  occupying  the  superior  two>thirds  of  the  bone,  and  called 
the  linea  aspera.  The  linea  aspera  begins  broad,  rough,  and 
flat,  on  a  level  with  the  trochanter  minor;  it  narrows  as  it  de- 
scends, and  becomes,  at  the  same  time,  more  elevated.  Its 
lower  extremity  bifurcates  into  two  superficial,  slightly  marked 
ridges,  one  on  ea'ch  side,  which  may  be  traced  into  the  poste- 
rior extremity  of  its  corresponding  condyle.  Between  these 
ridges  the  surface  of  the  bone  is  flattened.  In  the  whole  course 
of  the  linea  aspera,  an  internal  and  an  external  margin  is  very 
obvious.  The  superior  half  of  the  latter  is  occupied  by  the  in- 
sertion of  the  gluteus  magnus,  and  the  remainder  by  the  origin 
of  the  biceps  flexor  cruris.  This  margin  also  gives  origin  to 
the  vastus  externus.  The  internal  margin  of  the  linea  aspera 
is  mostly  occupied  by  the  insertion  of  the  triceps  adductor,  and 
by  the  origin  of  the  vastus  internus. 

In  the  linea  aspera,  near  the  middle  of  the  bone,  is  the  canal 
for  the  nutritious  artery,  which  slants  upwards :  occasionally 
one  or  more  canals,  besides,  are  found  in  it  for  the  same  pur- 
pose. 

The  texture  of  the  os  femoris  is  compact  in  its  body.  Its 
extremities  are  cellular,  with  the  exception  of  a  thin  lamina 
forming  their  periphery :  the  cylindrical  cavity  in  its  middle, 
like  that  in  all  the  other  long  bones,  is  reticulated.  The  ossa 
femorum  approach  each  other  very  closely  at  their  inferior  ex- 
tremities, but  are  widely  separated  at  their  superior,  in  conse- 
quence of  the  length  of  their  necks,  and  of  the  distance  of  the 
acetabula  from  one  another. 


THE  LEG.  217 


SECT.  II. — OF  THE  LEG. 


Two  bones  form  the  leg,  the  tibia  and  the  fibula,  to  which 
may  be  added  the  patella,  from  its  attachment  to  the  tibia. 


Of  the  Tibia,  (Tibia.) 

The  tibia  is  placed  at  the  internal  side  of  the  leg,  and  extends 
from  the  thigh  to  the  foot.  After  the  os  femoris,  it  is  the  long- 
est and  the  largest  bone  in  the  skeleton.  It  is  divided  into  the 
body  and  the  two  extremities. 

The  superior  extremity  of  the  tibia  is  oval,  transversely,  and 
presents  an  extent  of  surface  suited  to  the  articular  face  of  the 
two  condyles  of  the  os  femoris,  to  which  it  is  joined.  It  has 
here  two  superficial  cavities  for  receiving  the  ends  of  the  con- 
dyles; one  of  them  is  internal  and  the  other  external.  The  in- 
ternal is  the  deeper  and  more  extensive  of  the  two,  and,  being 
oval,  has  its  long  diameter  in  an  antero-posterior  direction. 
The  external,  besides  being  smaller  and  more  superficial,  is 
more  circular;  and,  from  the  want  of  elevation  in  its  margins, 
scarcely  presents  at  all  the  appearance  of  a  cavity.  These 
two  cavities,  which  approach  to  within  half  an  inch  of  each 
other,  are  kept  entirely  separated  by  an  elevated  triangular 
ridge,  with  a  broad  base,  called  the  spinous  process  of  the  tibia. 
The  summit  of  the  ridge  presents  two  tubercles,  one  at  each 
end,  separated  by  a  pit,  which  serves  to  attach  the  posterior 
end  of  the  external  semi-lunar  cartilage.  The  ridge  is  placed 
nearer  the  posterior  than  the  anterior  margin  of  the  tibia.  Its 
base,  in  front,  is  depressed  by  the  attachment  of  the  anterior 
crucial  ligament,  and  just  before  this  is  a  rough,  triangular 
space,  extending  to  the  anterior  margin  of  the  bone,  and  co- 
vered by  fat  in  the  recent  subject.  Between  the  ridge  and 
the  posterior  margin  of  the  bone  is  a  deep  depression  for  the 
attachment  of  the  posterior  crucial  ligament. 

The  circumference  of  the  superior  part  of  the  tibia,  just  be- 
low its  articular  surface,  is  flat  before,  somewhat  flat  and  con- 
VOL.  I.— 19 


218  SKELETON. 

cave  behind,  and  bulging  at  the  sides.  The  flatness,  in  front,  is 
triangular,  having  its  base  upwards  and  the  apex  downwards, 
the  latter  terminates  in  a  well  marked,  broad,  rough  rising, 
which  is  the  tubercle  of  the  tibia,  and  serves  for  the  insertion 
of  the  tendon  of  the  patella.  The  concavity  behind  is  made 
by  the  popliteus  muscle,  and  slopes  from  above  obliquely  in- 
wards and  downwards.  The  projection  is  great  on  the  inter- 
nal side  of  the  upper  extremity  of  the  tibia,  and  at  its  posterior 
part  has  a  depression  made  by  the  insertion  of  the  semi-mem- 
branosus  tendon.  The  external  projection  is  thicker  in  front 
than  behind;  at  the  latter  point  it  has  a  small  articular  face, 
looking  downwards,  for  the  head  of  the  fibula. 

The  inferior  extremity  of  the  tibia  is  much  smaller  than  the 
superior.  It  is  terminated  by  a  transverse  quadrilateral  cylin- 
drical concavity,  by  which  it  articulates  \vith  the  astragalus. 
This  concavity  is  narrower  and  deeper  internally  than  external- 
ly, and  is  traversed  from  before  backwards  by  a  low  broad  ridge. 
It  is  bounded  internally  by  the  internal  malleolus,  a  large  pro- 
cess of  half  an  inch  in  length,  the  external  side  of  which  is  a  con- 
tinuous surface  with  the  cylindrical  concavity,  and  forms  part 
of  the  joint.  The  other  side  of  the  malleolus  is  superficial,  being 
just  beneath  the  skin.  A  shallow  groove  exists  in  its  posterior 
part,  which  transmits  the  tendons  of  the  tibialis  posticus  and  of 
the  flexor  longus  digitorum  pedis.  Inferiorly,  the  malleolus  is 
notched,  or  presents  a  depression,  for  the  origin  of  the  internal 
lateral  ligament,  and  just  before  the  depression  it  is  elongated 
into  a  point.  The  lower  end  of  the  tibia  presents,  before  and 
behind,  a  slight  swell,  running  transversely  just  above  the  arti- 
cular surface.  The  posterior  swell  is  occasionally  slightly 
marked  by  the  tendon  of  the  flexor  longus  pollicis  pedis. 

Externally,  the  circumference  of  the  lower  end  of  the  tibia 
presents,  longitudinally,  a  concavity  which  is  in  contact  with 
the  lower  end  of  the  fibula.  This  concavity  .terminates  insen- 
sibly above,  but  is  deep  below,  where  it  is  bounded  before  and 
behind  by  an  elevated  point  of  bone,  of  which  the  posterior  is 
the  highest.  The  concavity  is  placed  nearly  in  the  vertical  line 
of  the  little  articular  face  for  the  fibula,  on  the  head  of  the  tibia; 
and  at  its  lower  margin,  there  is  frequently  a  small  lunated  sur- 


THE  LEG.  219 

face,  which  is  continuous  with  the  articular  surface  for  the  as- 
tragalus, and  is  consequently  a  part  of  the  cavity  of  the  ankle 
joint.  Just  above  this  lunated  surface  the  bone  is  rough  for  the 
origin  of  short  ligamentous  fibres,  which  unite  it  to  the  fibula. 

The  body  of  the  tibia  commences  just  below  the  enlarged  up- 
per extremity,  and  terminates  near  the  ankle.  In  the  front  view 
of  it,  it  diminishes  continually  in  descending,  in  its  superior  two- 
thirds:  afterwards  it  enlarges  gradually  to  the  lower  extremity; 
in  the  lateral  view  it  diminishes  downwards  almost  to  the  lower 
extremity.  It  is  slightly  bent  forwards,  and  is  generally  prisma- 
tic, more  particularly  above:  one  of  its  faces  is  internal,  another 
external,  and  the  third  posterior.  The  internal  face  is  rounded, 
and,  with  the  exception  of  its  upper  part,  where  the  flexor  ten- 
dons are  inserted,  it  is  only  covered  by  the  skin.  Its  external 
face  is  flat,  excepting  below,  where  it  is  rounded  and  is  covered 
by  the  muscles  on  the  front  of  the  leg.  The  posterior  face  is 
slightly  rounded,  except  at  its  upper  part  where  it  is  crossed  by 
a  line  running  obliquely  from  the  articular  surface  for  the  fibula, 
downwards  and  inwards :  above  which  line,  is  the  superficial 
triangular  depression  for  the  popliteus  muscle. 

The  three  sides  of  the  tibia  are  marked  off  from  each  other 
by  ridges  of  bone.  The  anterior  ridge,  called  the  spine  or  crest, 
begins  at  the  external  margin  of  the  tubercle  for  the  insertion 
of  the  tendon  of  the  patella,  and  may  be  traced  very  distinctly, 
in  the  form  of  an  S  very  slightly  curved,  almost  to  the  malleo- 
lusinternus:  it  is  more  elevated  in  its  middle.  The  external 
ridge  is  a  straight  line  running  from  one  extremity  of  the  bone 
to  the  other;  to  it  is  attached  one  edge  of  the  interosseous  liga- 
ment. The  internal  ridge  is  rounded,  but  also  runs  the  whole 
length  of  the  body  of  the  bone,  being  more  distinct  below.  The 
internal  lateral  ligament  of  the  knee  and  the  soleus  muscle  are 
attached  to  it,  above;  and  below,  the  flexor  longus  digitorum 
pedis. 

Foramina  large  and  small,  for  blood  vessels  and  fibres,  are 
found  on  the  circumference  of  both  extremities  of  the  tibia.  On 
its  posterior  face,  about  one-fourth  of  its  length  from  the  head, 
is  a  large  canal  sloping  downwards,  through  which  passes  the 
nutritious  artery.  Its  structure,  like  that  of  the  other  long  bones, 


220  SKELETON. 

is  cellular  at  its  extremities ;  but  compact  in  the  body,  where  it 
presents  a  cavity  occupied  by  cancellated  matter.  It  will  now 
be  understood  how  it  articulates  with  the  fibula,  externally,  at 
both  ends;  with  the  os  femoris  above;  and  with  the  astragalus 
below. 

Of  the  Fibula,  (Ptront.) 

The  fibula  is  placed  at  the  external  side  of  the  tibia,  and  ex- 
tends from  the  head  of  the  latter  to  the  foot :  it  is  much  smaller, 
and  not  quite  so  long  as  the  tibia,  and  is  so  articulated  with  it 
as  to  be  on  a  line  with  its  posterior  face.  It  is  to  be  studied  in 
its  two  extremities  and  in  its  body. 

The  upper  extremity  of  the  fibula  is  considerably  enlarged 
and  irregular.  It  presents,  above,  a  small  articular  face  di- 
rected upwards  and  very  slightly  concave,  by  which  it  joins  the 
corresponding  face  of  the  tibia.  This  surface  is  bounded  be- 
hind by  a  sort  of  styloid  process,  into  which  is  inserted  the  ten- 
don of  the  biceps  flexor  cruris.  The  circumference  of  the  bone, 
in  advance  of  this,  furnishes  attachment  to  the  external  lateral 
ligament  of  the  knee. 

The  inferior  extremity  of  the  fibula  is  also  enlarged,  being 
flattened  on  its  tibial  side,  but  more  rounded  externally.  This 
part  of  the  fibula  is  called  the  malleolus  externus.  It  descends 
lower  than  the  internal  ankle,,  and  is  also  more  prominent  and 
large.  Its  tibial  side  presents,  below,  a  small  triangular  slightly 
convex  articulating  surface,  which  reposes  against  the  side  of 
the  astragalus ;  behind,  and  somewhat  below  it,  is  a  small  rough 
depression,  which,  with  the  adjoining  inferior  margin  of  the  bone, 
gives  origin  to  the  three  fasciculi  of  the  external  lateral  ligament 
of  the  ankle.  Above  the  articular  surface,  the  bone  is  rough 
and  slightly  rounded  where  it  is  received  into  the  side  of  the 
tibia,  and  sends  oft'  many  short  ligamentous  fibres  to  it.  The 
anterior  margin  of  this  extremity  of  the  fibula  is  thin  and  pro- 
jecting, the  posterior  surface  is  flat  and  broad,  and  is  slightly 
scooped  out  into  a  longitudinal  groove,  which  transmits  the 
tendons  of  two  peronei  muscles.  The  pointed  termination 
below,  of  the  malleolus  externus,  is  sometimes  called  the  coro- 
noid  process. 


THE  LEG.  221 

The  body  of  the  fibula  extends  between  its  extremities.  It  is 
irregularly  triangular,  somewhat  smaller  above  than  below, 
thick  posteriorly,  thin  anteriorly,  and  slightly  convex  in  its 
length  behind. 

There  are  three  faces  to  the  fibula,  one  is  external,  another 
internal,  and  the  third  posterior.  The  first  is  semi-spiral,  and 
turned  forwards  above;  its  superior  third  gives  origin  to  the  pe- 
roneus  longus  muscle,  .and  the  middle  third  to  the  peroneus  se- 
cundus:  its  lower  third  exhibits  the  semi-spiral  arrangement 
which  may  be  traced  into  the  groove  on  the  posterior  part  of  the 
malleolus  externus,  and  thereby  indicates  the  course  of  the  ten- 
dons of  these  peronei  muscles.  The  internal  face  is  directed  to- 
wards the  tibia  ;  it  is  divided  by  a  low  longitudinal  ridge  into 
two  parts,  of  which  the  anterior  is  the  more  narrow.  The  ridge 
itself,  well  marked  in  the  middle  two-fourths  of  the  bone,  is  in- 
distinct above  and  below;  and  furnishes  attachment  to  the  inter- 
osseous  ligament.  The  space  in  front  gives  origin  to  the  exten- 
sor proprius  pollicis,  and  the  extensor  communis  digitorum  :  and 
the  space  behind  gives  origin  to  the  tibialis  posticus.  The  pos- 
terior face  is  also  somewhat  semi-spiral,  its  superior  end  being 
outwards,  and  the  inferior  end  inwards.  The  superior  third  gives 
origin  to  the  soleus  muscle,  and  the  remainder  to  the  flexor  lon- 
pollicis pedis. 


The  angles  of  the  fibula  which  are  formed  by  the  junction  of 
the  three  surfaces  described,  differ  somewhat  among  themselves. 
The  anterior  angle  is  frequently  very  sharp  and  elevated  in  its 
middle  half,  and  below  it  bifurcates  into  two  ridges,  including 
between  them  a  triangular  space,  which  is  only  covered  by  the 
integuments.  The  posterior  angle  is  well  marked,  and  winds 
so  as  to  be  external  above,  and  posterior  near  the  foot.  The 
internal  angle,  formed  by  the  union  of  the  internal  and  the  pos- 
terior surfaces,  is  only  very  well  marked  in  its  middle  half. 
The  projection  of  this  angle  gives  to  the  bone  the  appearance 
of  inclining  inwards  towards  the  tibia,  besides  which  it  has  ac- 
tually a  little  bend  in  that  direction. 

Near  the  middle  of  the  posterior  face  of  the  fibula,  a  canal, 
sloping  downwards,  conducts  the  nutritious  artery.  The  circum- 

19* 


222  SKELETON. 

ference  of  the  extremities,  like  that  of  the  other  long  bones,  pre- 
sents a  multitude  of  foramina  for  vessels  and  the  filaments  of 
fibres  to  pass.  It  is  composed  in  its  extremities  of  cellular  or 
spongy  structure,  and  in  its  body  of  compact  matter,  enclosing 
a  cavity  occupied  by  cancellated  structure. 

Of  the  Patella  (Rotule.) 

The  patella  is  a  small  bone,  intermediate  to  the  thigh  and  to 
the  leg,  and  placed  on  the  fore  part  of  the  knee  joint ;  it  is 
smaller  in  proportion  in  females  than  in  males. 

Its  anterior  face  is  uniformly  convex  and  rough,  and  is  studded 
with  a  considerable  number  of  foramina  for  the  passage  of  ves- 
sels, and  for  the  attachment  of  fibres.  The  course  of  the  longi- 
tudinal fibres  composing  the  front  of  the  bone,  is  also  well  marked. 
The  posterior  face  of  the  patella  is  an  extensive  articular  sur- 
face, divided  unequally  by  a  broad  longitudinal  elevation,  which 
runs  from  the  superior  to  the  inferior  margin  of  the  bone.  The 
part  of  this  surface  external  to  the  ridge,  is  the  largest  and  the 
most  concave,  and  is  applied  to  the  trochlea,  in  front  of  the  ex- 
ternal condyle  of  the  os  femoris  ;  while  the  smaller  surface  is 
on  the  internal  side  of  the  ridge,  and  is  applied,  to  the  trochlea, 
of  the  internal  condyle. 

The  circumference  of  the  patella  is  nearly  oval,  the  long  di- 
ameter being  transverse.  Its  thickness  is  much  augmented 
above,  where  it  presents  a  rough,  and  somewhat  unequal  flatness 
for  the  insertion  of  the  tendon  of  the  rectus  femoris.  Below, 
the  bone  is  thinner,  and  elongated  into  a  conical  point,  from 
which  proceeds  the  tendon  of  the  patella  to  be  inserted  into  the 
tibia.  Laterally,  the  margins  are  thinner  still. 

The  texture  of  the  patella  is  cellular,  covered  by  a  lamina  of 
condensed  bony  matter.  It  is  developed  in  the  tendon  of  the 
extensors  of  the  thigh,  and  with  the  exception  of  its  posterior 
face  remains  in  a  state  almost  entirely  cartilaginous,  for  a  year 
or  two  after  birth.  Its  base  is,  therefore,  fibrous,  in  which  is 
deposited,  subsequently,  the  calcareous  matter.  In  its  fracture 
union  is  effected  more  frequently  by  the  fibrous  base  alone, 
than  by  perfect  ossification.  In  order  to  put  it  into  its  proper 


THE  FOOT.  223 

position,  turn  the  point  downwards,  and  apply  the  greater  sur- 
face behind,  to  the  trochlea  of  the  external  condyle.  The  pa- 
tella is  said  to  be  to  the  tibia,  what  the  olecranon  is  to  the 
ulna;  and  is,  therefore,  a  sort  of  appendage  to  it,  united  by 
ligament  instead  of  being  continuous  with  it,  as  is  the  case  with 
the  olecranon. 


SECT.  111.: — OF  THE  FOOT. 

The  foot  forms  the  third  section  of  the  inferior  extremity,  and 
is  placed  at  a  right  angle  to  the  bones  of  the  leg.  The  size  of 
its  bones  varies  much  in  different  individuals,  depending  much 
upon  their  modes  of  life,  and  dress :  it  also  varies  much  in  the 
two  sexes,  being,  for  the  most  part,  smaller  in  the  female. 
The  foot  is  oblong,  narrower  behind  than  before ;  presents  one 
surface  above,  which  is  its  back,  and  another  below,  which 
is  the  sole;  a  posterior  extremity  called  the  heel,  and  an  ante- 
rior extremity  called  the  point;  also  its  internal  margin  is  much 
thicker,  longer  and  more  concave,  than  the  external  margin. 

The  foot  is  divided  into  Tarsus,  Metatarsus,  and  Toes  or 
Phalanges. 


o 


Of  the  Tarsus,  (Tar se.) 

The  tarsus  forms  the  posterior  half  of  the  foot,  and  is  com- 
posed of  seven  distinct  bones,  which  are  arranged  on  a  plan, 
and  present  features  having  scarcely  a  single  point  of  resem- 
blance with  the  carpus.  These  bones  are,,  the  Os  Calcis,  the 
Astragalus,  the  Naviculare,  the  Cuboides,  the  Cuneiforme  Ex- 
ternum,  Cuneiforme  Medium,  and  Cuneiforme  Internum. 


Of  the  Os  Calcis,  (Cakaneum.) 

The  calcaneum,  or  heel  bone,  forms,  almost  exclusively,  the 
posterior  half  of  the  tarsus,  and  may  be  readily  distinguished 
by  its  greater  magnitude.  Its  shape  is  very  irregular.  Its 
greatest  diameter  is  in  the  length  of  the  foot;  it  is  also  thicker 
vertically  than  transversely. 


224  SKELETON.  » 

The  superior  face  is  deeply  scooped  out,  at  its  fore  part,  and 
is  formed  there  into  two  articular  surfaces,  for  joining  with  the 
astragalus:  these  faces  are  separated  from  each  other  by  a  rough 
fossa,  which  runs  from  within  obliquely  forwards  and  outwards. 
The  anterior  external  part  of  this  fossa  is  deep,  broad,  and  tri- 
angular; the  posterior  part  is  narrow,  is  occupied  by  a  ligament, 
and  allows  the  two  articular  surfaces  to  come  nearer.  Just 
behind  the  fossa  is  the  first  articulating  surface,  lying  parallel 
with  it;  being  oblong,  convex,  semi-cylindrical,  and  looking 
obliquely  upwards  and  forwards.  Before  the  fossa  is  the  se- 
cond surface:  it  is  oblong,  much  smaller  than  the  first,  and  is 
very  frequently  divided  into  two  by  a  transverse  notch,  and  is 
concave.  The  part  of  the  bone  upon  which  this  face  is  wrought, 
is  called,  by  the  French,  the  little  apophysis.  I  have  frequent- 
ly remarked,  that  the  face  posterior  to  the  first  mentioned  fossa 
is  smaller  and  more  vertical  in  the  African  than  in  the  Eu- 
ropean; the  os  calcis,  behind  it,  is  also  smaller  and  longer. 
The  upper  posterior  face  of  the  bone  is  somewhat  concave. 

The  under  surface  of  the  os  calcis  is  slightly  concave,  longi- 
tudinally. It  is  bounded,  behind,  by  two  tuberosities,  of  which 
the  internal  is  larger  than  the  external;  they  both  give  origin 
to  muscles  of  the  sole  of  the  foot  and  to  the  aponeurosis 
plantaris.  There  is  also  a  tuberosity  bounding  the  same  sur- 
face in  front,  from  which  arise  the  ligaments  that  connect  this 
bone  with  the  adjoining  ones.  . 

The  anterior  extremity  of  the  os  calcis  forms  the  greater 
apophysis,  and  is  terminated  in  front  by  a  triangular  and  slight- 
ly concave  surface,  by  which  it  articulates  with  the  os  cu- 
boides.  The  posterior  extremity  is  convex  and  rough :  con- 
stitutes the  heel,  and  near  its  middle  receives  the  tendo-achillis; 
the  upper  part  is  sloping  and  more  smooth,  in  order  to  accom- 
modate this  tendon  in  the  flexions  of  the  foot. 

The  external  surface  of  the  os  calcis  is  flat,  with  the  excep- 
tion of  a  gentle  rising  in  its  middle;  it  is  marked,  occasionally, 
by  a  superficial  groove,  indicating  the  course  of  the  peronei 
muscles.  The  internal  surface  is  very  concave,  and  obtains  the 
name  of  sinuosity;  along  it  pass  the  tendons  of  several  muscles 


THE  FOOT.  225 

from  the  back  of  the  leg,  of  which  that  of  the  flexor  longus  pol- 
iicis  pedis  makes  a  conspicuous  groove  on  the  under  surface  of 
the  little  aphophysis. 

Of  the  Astragalus,  (UJlstragah.) 

This  is  the  next  in  size  to  the  os  calcis,  and  is  placed  on  the 
superior  part  of  the  latter,  between  it  and  the  bones  of  the  leg, 

The  astragalus  presents,  above,  a  semi-cylindrical  surface, 
by  which  it  is  put  in  contact  with  the  tibia.  This  surface  is 
narrower,  and  continued  farther  behind  than  it  is  before;  is 
slightly  depressed,  longitudinally,  in  its  middle,  and,  conse- 
quently, presents  an  elevated  margin  on  either  side,  of  which 
the  external  is  the  broadest  and  highest.  This  articular  face 
continues  on  each  side  of  the  bone,  and  is  more  extensive  ex- 
ternally, where  it  comes  in  contact  with  the  fibula  or  malleolus 
externus,  than  internally,  where  it  touches  the 'malleolus  in- 
ternus. 

The  inferior  face  of  the  astragalus  is  traversed  by  an  oblique 
rough  fossa,  going  from  within  outwards  and  forwards,  and 
corresponding  in  size  with  that  on  the  upper  face  of  the  os  cal- 
cis. Behind  the  fossa,  and  parallel  to  it,  is  a  deep  oblique  se- 
mi-cylindrical concavity,  suited  to  the  adjoining  face  of  the  os 
calcis;  and  before  the  fossa  is  a  narrow  oblong  convexity, 
suited  to  the  corresponding  articular  concavity  of  the  same 
bone.  When  the  latter  is  divided  into  two  facets,  the  concavi- 
ty of  the  astragalus  presents  also  two  facets,  separated  by  a 
small  ridge. 

The  anterior  extremity  of  this  bone  is  terminated  by  a  con- 
vex head,  the  horizontal  diameter  of  which  is  the  greatest. 
This  head  articulates  with  the  scaphoides,  and  is  continuous 
with  the  surface  that  rests  upon  the  little  apophysis  of  the  os 
calcis.  On  the  internal  side  of  the  head  is  a  small  triangular 
surface,  continuous  with  the  others,  that  rests  upon  a  strong 
ligament  going  from  the  os  calcis  to  the  scaphoides.  Above, 
immediately  before  the  surface  for  the  tibia,  is  a  small  depres- 
sion, which,  in  the  flexions  of  the  foot,  receives  the  anterior 


226  SKELETON. 


margin  of  the  articular  surface  of  that  bone.  The  posterior 
extremity  of  the  astragalus  is  thin,  and  has  a  notch,  or  groove, 
formed  in  it  by  the  tendon  of  the  flexor  longus  pollicis. 


Of  the  Naviculare,  or  Scaphoides,  (Scaphoide.) 

It  is  situated  at  the  internal  side  of  the  tarsus,  between  the 
astragalus  and  the  cuneiform  bones,  and  has  its  greatest  dia- 
meter transverse.  Its  circumference  is  oval,  thicker  above 
than  below,  and  at  its  internal  side  presents  a  large  tuberosity; 
into  which  is  inserted  the  tendon  of  the  tibialis  posticus.  Some- 
times the  external  margin  has  a  small  articular  face,  where  it 
comes  in  contact  with  the  cuboides. 

The  scaphoides  presents,  behind,  a  deep  concavity,  which 
receives  the  head  of  the  astragalus;  anteriorly,  it  is  somewhat 
convex,  but  this  surface  is  divided  by  small  ridges  into  three 
triangular  faces,  for  the  three  cuneiform  bones.  Of  these  faces 
the  internal  is  broader  below  than  above;  the  others  are  broader 
above  than  below. 


Of  the  Cuboides,  (Cuboide.) 

It  is  situated  at  the  external  side  of  the  tarsus,  between  the 
os  calcis  and  the  metatarsal  bones.  Its  figure  is  irregular;  but, 
perhaps,  sufficiently  indicated  by  its  name.  It  is  narrower 
externally  than  internally,  and  has  the  posterior  extremity 
oblique. 

The  superior  face  of  the  cuboides  is  rounded,  but  rough. 
The  inferior  face  has  in  its  middle  a  broad  elevated  ridge  run- 
ning almost  transversely,  but  somewhat  forwards.  The  exter- 
nal extremity  of  this  ridge  is  marked  by  a  trochlea,  on  which 
plays  the  tendon  of  the  peroneus- longus;  the  tendon  is  then  con- 
ducted along  a  groove  between  the  ridge  and  the  anterior  mar- 
gin of  the  bone. 

The  internal  face  is  flat,  and  has  in  its  middle  a  circular 
facet  where  it  comes  in  contact  with  the  cuneiforme  externum. 


THE  FOOT.  227 


The  posterior  face  joins  the  os  calcis,  is  triangular,  and  semi- 
spiral.  The  anterior  face  is  oblong,  transversely,  and  is  di- 
vided by  a  slight  vertical  rising  into  two,  for  articulating  with 
the  last  two  metatarsal  bones. 


Of  the  Qunerforme  Internum,  (Premier  Cuneiforme.) 

It  is  placed  at  the  internal  anterior  extremity  of  the  tarsus? 
between  the  scaphoides  and  the  first  metatarsal  bone,  and  may 
be  distinguished  from  the  other  cuneiforms  by  its  greater  size. 
Its  thickest  part  is  below. 

The  anterior  face  presents  a  long  vertical  convexity,  which 
joins  the  first  metatarsal  bone.  The  posterior  face  is  not  so 
extensive,  and  is  formed  into  a  triangular  concavity,  having 
the  broadest  part  below,  which  joins  the  internal  facet  of  the 
scaphoides.  The  internal  side  is  semi-cylindrical  and  rough; 
it  is  marked,  anteriorly,  near  its  middle,  by  the  tendon  of  the 
tibialis  anticus.  The  external  side  is  somewhat  concave,  and 
generally  rough,  and  is  marked  just  below  its  superior  margin 
by  two  articular  facets,  of  which  the  anterior  is  the  smaller, 
and  comes  in  contact  with  the  second  metatarsal  bone;  the 
posterior,  from  its  concave  obliquity,  gives  a  slope  to  the  upper 
margin  of  the  bone,  and  is  in  contact  with  the  cuneiforme  me- 
dium. 

Of  the  Cuneiforme  Medium,  (Second  Cuneiforme.) 

The  middle  or  second  cuneiform  bone  is  placed  upon  the 
scaphoides,  immediately  on  the  outside  of  the  cuneiforme  in- 
ternum.  It  may  be  distinguished  by  being  the  smallest  bone  of 
the  tarsus.  Its  figure  resembles  sufficiently  well  a  wedge;  the 
base  of  which  is  above,  and  the  edge  below. 

Its  posterior  face  is  slightly  concave  where  it  joins  the  sca- 
phoides; the  anterior  face  is  slightly  convex,  and  articulates 
with  the  second  metatarsal  bone.  The  internal  face  presents, 
superiorly,  an  oblong,  slightly  convex,  and  oblique  articular 
facet,  which  touches  the  cuneiforme  internum:  what  remains 
of  this  side  is  rough,  for  the  origin  of  Jigamentous  fibres.  The 


228  SKELETON. 

external  face  is  somewhat  concave,  and  presents,  at  its  poste- 
rior part,  a  vertical  articular  face  for  joining  the  cuneiforme 
externum ;  but  anteriorly,  it  is  rough  for  the  origin  of  ligamen- 
tous  fibres. 

In  the  articulated  foot  the  lower  part  of  this  bone  is  almost 
concealed  between  the  other  two  cuneiforms. 

Of  the  Cuneiforme  Externum,  (Troisieme  Cuneiforme.') 

The  external  or  third  cuneiform  bone  is  placed  upon  the  sca- 
phoides,  between  the  second  cuneiform  and  the  cuboides.  Of 
the  three  bones  it  is  the  second  in  size,  and  is  also  appropriate- 
ly named  from  its  shape.  The  base  is  upwards. 

The  posterior  face  furnishes,  on  its  superior  half  to  join  the 
scaphoides,  a  quadrangular  articular  facet,  sloping  outwardly, 
below  which  the  bone  projects  into  the  sole  of  the  foot.  The 
anterior  face  is  flat,  and  articulates  with  the  third  metatarsal 
bone.  The  internal  face  presents,  above,  two  articular  facets, 
of  which  the  one  at  the  posterior  corner  is  larger  than  the  other, 
and  joins  the  second  cuneiform;  the  other,  at  the  anterior  cor- 
ner, is  very  small,  and  touches  the  second  metatarsal  bone. 
Below  these  facets  the  bone  is  rough,  and  gives  origin  to  liga- 
mentous  matter.  The  external  face,  at  the  middle  of  the  base, 
forms  an  angular  projection,  behind  which  is  a  small  oval  arti- 
cular surface  that  joins  the  cuboides.  The  remainder  of  this 
face  is  rough,  for  the  origin  of  the  ligaments,  with  the  excep- 
tion of  a  very  small  articular  facet  at  the  anterior  superior  cor- 
ner, which  joins  the  fourth  metatarsal  bone. 


The  structure  of  the  bones  of  the  Tarsus  is  uniformly  cellu- 
lar within,  the  cells  being  enclosed  by  a  thin  lamina  of  con- 
densed matter.  The  astragalus  is  rather  stronger  and  more 
compact  than  any  of  the  others.  I  have  seen  one  instance, 
however,  in  which  it  had  been  separated  into  two  pieces  by  a 
transverse  vertical  fracture,  going  from  the  ankle  joint  to  the 
articulation  with  the  os  calcis.  The  observation  was  made 
after  it  had  been  boiled:  the  callus  had  completely  united  the 
two  fragments,  and  no  displacement  had  occurred. 


THE  TOOT, 

If  a  vertical  section  of  the  os  calcis  and  of  the  astragalus  be 
made,  the  parietes  of  these  cells  are  found  to  radiate  from  the 
upper  articular  surfaces  like  columns,  so  as  to  prevent  the 
bones  from  being  crushed  by  the  vertical  weight  of  the  body. 

Of  the  Metatarsus,  (Metatarse.) 

The  metatarsus  succeeds  to  tho  tarsus,  and  is  formed  by  five 
long  parallel  bones.  They  are  called  numerically,  beginning 
on  the  inner  side,  or  that  of  the  great  toe.  There  are  four  in- 
tervals between  them,  which  are  filled  up  by  the  inter  osseous 
'muscles. 

Of  the  First  Metatarsal  Bone. 

Placed  at  the  inner  side  of  the  foot  upon  the  cuneiforme  ifi- 
ternum,  and  forming  the  base  of  the  great  toe,  it  may  be  readi- 
ly distinguished  in  the  separated  bones  by  its  greater  size  and 
shortness. 

The  posterior  -extremity  presents  an  oblong  articular  conca- 
vity, the  greatest  length  of  which  is  vertical,  for  joining  the  cu- 
neiforme internum.  The  internal  semi-circumference  of  this 
extremity  is  convex,  while  the  external  is  slightly  concave  or 
flat;  below,  it  presents  a  prominent  tubercle,  into  which  is  in- 
serted the  tendon  of  the  peroneus  longus. 

The  anterior  extremity,  also  called  the  head,  is  rounded  and 
convex,  forming  an  articular  surface  for  the  first  phalanx  of  the 
great  toe.  This  surface  is  continued  far  back  below,  and  pre- 
sents there,  for  the  sesamoid  bones,  a  trochlea  with  a  longitu- 
dinal ridge  in  its  middle.  The  lateral  surfaces  of  the  head  arc 
rough  and  concave,  for  the  origin  of  the  lateral  ligaments. 

The  body  is  much  smaller  than  the  extremities,  and  is  pris- 
matic. Its  internal  side  is  rounded,  the  external  side  flattened, 
and  the  inferior  side  concave,  longitudinally,  for  lodging  the 
muscles  of  the  great  toe. 

VOL.  I.— 20 


230  SKELETON. 

Of  the  Second  Metatarsal  Bone. 

This  is  the  longest  of  any,  and  may  be  distinguished  from  the 
others  principally  by  that  circumstance. 

The  posterior  extremity  is  triangular,  the  broadest  part  being 
above.  It  presents  a  surface  very  slightly  concave,  almost  flat, 
which  rests  upon  the  cuneiforme  medium.  The  sides  of  this 
extremity  being  flattened,  laterally,  it  is  locked  in  between  the 
internal  and  external  cuneiforms ;  on  its  internal  side,  above,  is 
an  articular  facet,  where  it  comes  in  contact  with  the  cunei- 
forme intemum,  and,  externally,  it  has  two  articular  facets.  The 
posterior  one  of  the  latter  touches  the  cuneiforme  externum, 
and  the  anterior,  which  is  smaller,  comes  in  contact  wi'th  the 
third  metatarsal  bone.  These  two  facets  run  into  each  other 
by  an  angular  rising. 

The  anterior  extremity  is  convex  and  rounded;  its  vertical 
diameter  is  more  considerable  than  its  transverse,  and  the  arti- 
cular face  which  it  furnishes  to  the  second  toe  is  continued  con- 
siderably below,  in  order  to  assist  the  flexion  of  the  first  phalanx. 
Its  circumference  is  rough  and  flattened  laterally,  for  the  origin 
of  the  capsular  ligament. 

The  body  is  smaller  than  either  of  the  extremities,  and  de- 
creases gradually  from  behind  forwards.  It  is  flattened  on  each 
side,  and  elevated  longitudinally  above  and  below,  into  a  ridge. 
There  is  a  curvature  in  its  length,  which  makes  it  convex  above, 
and  concave  below,  for  the  lodgement  of  muscles. 

Of  the  Third  Mvtalarsal  Bone. 

This  is  rather  shorter  than  the  second,  but  has  very  much 
the  same  shape. 

Its  posterior  extremity,  or  base,  is  triangular,  has  the  broad- 
est part  above,  and  articulates  with  the  third  cuneiform;  the 
surface  for  the  latter,  slopes  outwardly.  Its  circumference  is 
flattened  laterally,  and  presents,  internally,  at  its  superior  cor- 


THE  FOOT.  231 

ner,  a  small  face,  which  articulates  with  the  second  metatar- 
aal;  externally,  it  also  presents,  at  its  superior  corner,  an  arti- 
cular facet,  which  joins  the  fourth  metatarsal. 

Its  body  and  anterior  extremity,  do  not  present  any  essen- 
tial points  of  difference  from  the  second  metatarsal. 


Of  the  Fourth  Metatarsal  Bone. 

It  is  somewhat  shorter  than  the  third,  and  is  placed  upon  the 
internal  of  the  two  anterior  faces  of  the  cuboides. 

The  posterior  extremity,  or  base,  is  more  quadrangular  than 
the  base  of  the  preceding  bones.  It  presents  an  articular  face 
to  the  cuboides,  which  is  also  square  or  nearly  so,  flat,  and  slopes 
outwardly.  On  its  sides  it  is  irregular ;  internally,  at  the  superior 
margin,  it  has  two  articular  facets,  continuous  with  each  other, 
but  forming  thereby  an  obtuse  angle;  the  anterior  joins  the  third 
metatarsal;  and  the  posterior,  which  is  much  the  smaller,  touches 
the  cuneiforme  externum.  Below  these,  the  surface  is  rough. 
The  articulation  with  the  cuneiforme  externum  is  occasionally 
deficient.  I  have  observed  the  latter,  particularly  in  the  negro, 
and  it  seems  to  arise  from  the  unusual  development  of  the  cu- 
boides. The  external  surface  of  the  base  has  at  its  superior 
corner  an  articular  facet  for  the  fifth  metatarsal  bone,  and  be- 
lo\v  it  an  oblique  deep  fossa,  before  which  is  a  tubercle. 

The  anterior  extremity  and  the  body  of  this  bone,  though 
smaller  than  those  of  the  preceding,  do  not  present  any  essen- 
tial points  of  difference. 


Of  the  Fifth  Metatarsal  Bone. 

.This  is  shorter  than  any  of  the  others,  excepting  the  first,  and 
is  placed  on  the  front  of  the  cuboides,  externally. 

Its  base  is  remarkable,  and  distinguishes  it  strongly,  by  being 
projected  considerably  beyond  the  external  margin  of  the  cu- 
boides, and  forming  there  a  large  tubercle,  into  the  superior  part 


SKELETOX. 


of  which  is  inserted  the  tendon  of  the  peroneus  tertius,  and  into 
the  posterior  part,  the  tendon  of  the  peroneus  secundus.  The 
base,  also,  has  a  triangular  flat  surface,  sloping  considerably 
outwards,  which  articulates  with  the  cuboides.  On  the  inter- 
nal side  is  the  articular  facet,  whereby  it  joins  the  base  of  the 
fourth  rnetatarsal  bon-e.  The  base  is  flattened  below,  rough, 
and  somewhat  convex  above.  N 

The  anterior  extremity  is  more  rounded  than  that  of  the  other 
metatarsal  bones,  but  in  other  respects  similar.  The  body  is 
prismatic  ;  being  flat  below,  flat  internally,  and  slightly  rounded 
externally. 

Of  the  Toes. 

The  toes  are  five  in  number,  and  named  numerically,  by  be- 
ginning at  the  great  one.  They  each  are  formed  by  three  bones 
called  the  phalanges,  with  the  exception  of  the  great  toe,  which 
has  but  two  of  them.  The  phalanges  are  distinguished  into  first, 
second,  and  third.  In.  these  several  respects  the  toes  correspond 
with  the  fingers. 

Of  the  First,  or  Great  Toe. 

The  first  phalanx  of  the  great  toe  is  longer  and  much  larger 
than  any  other.  Its  base  is  large,  and  forms  a  deep  concavity 
for  receiving  the  end  of  tke  metatarsal  bone.  Its  anterior  ex- 
tremity is  formed  into  two  small  condyles,  for  being  received 
into  the  second  phalanx.  This  bone  is  broad  and  strong,  being 
semicylindrical  above,  and  flat  below. 

The  second  phalanx  corresponds  in  its  appearance  with  the 
third  of  the  other  toes,  but  is  much  larger  than  any  of  them.  Its 
base  is  broad  and  flat,  and  has  two  superficial  cavities  for  the 
condyles  of  the  first  phalanx.  The  anterior  extremity  is  ex- 
panded semicircularly,  and  converted  into  a  very  scabrous  sur- 
face, for  the  firmer  attachment  of  the  soft  parts  about  it.  The 
body  of  this  phalanx  is  constricted  in  the  middle,  rounded 
above,  and  flat  below. 

Connected  with  the  great  toe,  are  two  small  hemispherical 
bones,  lying  upon  the  trochlea  of  its  metatarsal  bone,  and  im- 


THE  FOOT.  233 

bedded  in  the  tendons  of  the  small  muscles  which  move  the  first 
phalanx.  They  are  the  sesamoids,  and  present,  superiorly,  an 
articular  surface,  covered  with  cartilage,  which  enters  into  the 
composition  of  the  joint;  and  below,  a  rounded  surface,  which 
has  nothing  remarkable. 

The  sesamoid  bones,  though  generally  appropriated  solely  to 
this  joint,  are  yet  frequently  found  elsewhere.  For  example,  in  the 
second  joint  of  the  same  toe — in  the  first  joint  of  the  other  toes 
—in  the  articulation  of  the  first  phalanx  of  the  thumb,  with  its 
metacarpal  bone— in  the  first  joint  of  the  fingers— in  the  knee 
joint,  behind  each  condyle — and,  in  advanced  life,  in  tendons 
where  they  slide  upon  bones.  Ancient  luxations  give  a  dispo- 
sition to  their  development  in  the  capsular  ligaments  of  the  gin- 
glymous  joints,  of  which  a  very  interesting  specimen  may  be 
seen  in  the  Anatomical  Museum,  occasioned  by  an  external  la- 
teral dislocation  of  the  elbow. 

Of  the  Smaller  Toes. 

Their  phalanges  bear  a  general  resemblance  with  those  of  the 
fingers,  but  are  neither  so  large  nor  so  long. 

The  first  phalanges  are  successively  diminished  to  that  of  the 
little  toe,  and  are  almost  precisely  like  each  other.  Their  pos- 
terior extremities,  or  bases,  form  a  cavity  deeper  in  proportion 
than  in  the  fingers,  for  receiving  the  ends  of  the  metatarsal 
bones.  The  anterior  extremities  are  fashioned  into  two  small 
condyles  forforming  a  hinge-like  joint  with  the  second  phalanges. 
The  bodies  are  smaller  than  the  extremities,  more  rounded  and 
narrower  than  in  the  fingers. 

The  second  phalanges  are  very  short,  the  extremities  being 
so  near  each  other  that  the  body  is  of  inconsiderable  length,  par- 
ticularly as  regards  the  last  two,  where  it  forms  a  mere  line  of 
separation.  The  posterior  end  has  two  superficial  cavities  for 
receiving  the  first  phalanx;  the  anterior  end  is  imperfectly  fa- 
shioned into  two  little  condyles  for  joining  the  third  phalanx. 

The  third  phalanges  have  a  well-formed  articular  surface  for 

20* 


234  SKELETON. 

joining  the  second.  The  anterior  extremity  is  rough,  for  the  at* 
tachment  of  the  adjoining  soft  structure.  This  phalanx  of  the 
fourth  and  fifth  toe  is  frequently  very  imperfectly  developed,  be- 
ing a  mere  tubercle  with  an  articular  face  at  one  end. 

The  structure  of  the  metatarsal  and  phalangial  bones  resem- 
bles that  of  other  long  bones.  Porous  and  cellular  at  the  ex- 
tremities, their  bodies  are  composed  of  compact  lamellated  mat- 
ter, enclosing  a  cancellated  texture. 


SECT.  IV. OF  THE  DEVELOPMENT  OF  THE  INFERIOR  EXTREMITIES. 

The  comparatively  small  quantity  of  blood  which  is  sent  to  the 
lower  extremities  of  the  foetus,  is  the  cause  of  their  not  being  so 
large  in  proportion  to  the  upper,  at  the  time  of  birth,  as  they  are 
subsequently.  Our  wants  immediately  after  birth,  and  during 
the  first  months  of  life,  are  naturally  such  as  to  require  but  little 
service  from  the  lower  extremities,  in  which  is  seen  a  striking 
correspondence  between  the  internal  arrangements  of  the  animal 
economy  and  its  actual  necessities;  or,  in  other  words,  a  conti- 
nued and  rigid  adaptation  of  means  to  produce  a  certain  effect. 

The  os  femoris  at  birth  presents  several  peculiarities.  The  su- 
perior extremity  being  in  a  cartilaginous  state,  is  placed  more  at 
:«.  right  angle  to  the  body  of  the  bone  than  it  is  in  the  adult.  The 
neck  is  short,  which  by  diminishing  the  base  of  support  to  the' 
trunk,  makes  the  progression  of  infants  more  tottering  and  infirm. 
The  lower  extremity  is  also  cartilaginous  and  large.  The  body 
of  the  bone  has  but  a  very  slight  degree  of  curvature,  which  like- 
wise increases  the  difficulty  of  standing  and  walking  in  very 
young  subjects.  The  patella  is  cartilaginous. 

In  the  leg  the  bodies  of  the  tibia  and  fibula  are  ossified,  but 
their  extremities  are  cartilaginous.  The  bones  of  the  tarsus, 
with  the  exception  of  parts  of  the  os  calcis  and  of  the  astragalus 
are  cartilaginous.  The  metatarsus  and  the  phalanges  are  ossi- 
fied in  their  middle,  but  cartilaginous  at  their  extremities:  their 
development  is  not  so  complete  as  that  of  the  corresponding 
bones  of  the  hand. 


MECHANISM  OF  THE  INFERIOR  EXTREMITIES.  235 

About  the  fifteenth  year,  the  bones  of  the  lower  extremities 
have  very  nearly  the  same  forms  as  in  the  adult:  they  are  all  fully 
ossified,  with  the  exception  of  their  extremities  not  being  fused 
or  joined  to  their  bodies;  but  still  in  the  state  of  epiphyses,  and, 
therefore,  separable  either  by  boiling  or  long-continued  macera- 
tion.' Exclusively  of  this  condition,  which  sometimes  remains  to 
the  twentieth  or  tWenty-fifth  year,  the  epiphyses  are  as  fully  os- 
sified as  at  any  subsequent  period  of  life. 


SECT.  V. ON  THE  MECHANISM  OF  THE  INFERIOR  EXTREMITIES  IN 

REGARD  TO  STANDING. 

The  os  femoris  is  well  adapted  by  its  shape  and  position  to 
the  erect  attitude.  The  curvature  which  its  body  makes  in 
front  has  the  effect  of  advancing  the  lower  part  of  it,  and  there- 
by keeping  it  in  a  line  with  the  centre  of  the  trunk;  but  if  it  had 
been  perfectly  straight,  the  erect  position  would  have  been  main- 
tained with  great  difficulty,  owing  to  the  centre  of  the  trunk 
being  in  advance  of  this  bone.  Under  the  latter  circumstancea, 
an  incessant  tendency  to  fall  forwards  would  have  manifested 
itself,  which  could  have  been  obviated  only  by  flexing  the  ossa 
femorurn  very  much  at  the  hip  joint,  or  by  keeping  one  foot  al- 
ways in  front  of  the  other.  Even  under  the  actual  arrangement 
of  the  skeleton,  when  muscular  support  is  withdrawn  from  it  sud- 
denly, it  falls  forwards,  owing  to  the  weight  of  the  parts  anterior 
10  the  spine  being  greater  than  that  of  the  parts  posterior  to  it. 
When  muscular  action  is  weakened  or  badly  regulated,  the  same 
tendency  to  fall  forwards  is  manifested :  children  continually 
tumble  in  that  direction:  a  person  in  a  state  of  intoxication, 
somewnat  short  of  the  entire  loss  of  locomotion,  not  being  able 
to  sustain  the  trunk  of  the  body  erect  by  the  muscles  of  the 
back,  inclines  forwards,  and  would  be  precipitated  to  the  ground, 
were  it  not  that  at  this  crisis  one  leg  is  involuntarily  advanced, 
so  that  the  base  of  support  is  much  augmented.  But  if  the  in- 
dividual attempt  to  walk,  the  continued  necessity  of  keeping  a 
large  basis  of  support  to  prevent  the  body  from  falling  forwards, 
urges  him  into  a  slow7  running  or  trotting  gait. 

The  arrangement  of  the  whole  upper  extremity  of  the  os  fe- 


236  SKELETON. 

moris  is  also  highly  favourable  to  the  erect  attitude  and  to  loco- 
motion. The  neck  of  the  bone,  by  its  length  and  oblique  posi- 
tion in  regard  to  its  body,  enlarges  transversely  the  base  of  its 
support,  and  gives  great  stability  in  preventing  the  trunk  from 
falling  either  to  the  right  or  left;  while  it  contributes  at  the  same 
time  to  the  facility  of  progression,  in  permitting  the  os  femoris  to 
bend  forwards  and  backwards.  The  laterat  or  transverse  extent 
of  the  base,  thus  obtained,  cannot  be  supplied  with  equal  effect 
in  any  other  way,  as  a  certain  proportion  between  the  diameters 
of  the  pelvis  and  the  length  of  the  neck  of  the  thigh  bone  is  in- 
dispensable. In  females,  where  the  transverse  diameter  of  the 
pelvis  is  greater  than  in  males,  though  standing  is  equally  secure 
as  in  the  latter,  yet  their  progression  is  always  marked  by  a 
want  of  firmness  strongly  characteristic  of  the  sex.  The  strength 
of  articular  connexion  of  the  os  femoris  with  the  innominatum  is 
confirmed  by  the  acetabulum  being  placed  where  the  latter  is 
re-enforced  by  the  linea  ilio  pectinea,  and  by  the  anterior  infe- 
rior spinous  process;  and  as  the  principal  weight  of  the  trunk  is 
sustained  by  the  acetabulum,  immediately  below  the  latter  pro- 
cess, we  accordingly  find  it  at  this  point  of  the  greatest  depth. 
It  is  also  to  be  stated,  that  the  capsular  ligament  at  this  part  is 
stronger  than  elsewhere,  thereby  conforming  strictly  to  the  gene- 
ral purposes  of  the  articular  connexion.  The  capsular  ligament 
is  assisted  by  the  ligamentum  teres,  which,  by  arising  from  the 
lower  margin  of  the  acetabulum  and  passing  upwards  to  the 
head  of  the  os  femoris,  prevents  the  head  from  sliding  upwards, 
while  it  permits  it  to  swing  freely  backwards  and  forwards  in 
its  socket. 

In  erection,  the  bones  of  the  leg  are  in  a  line  with  the  vertical 
diameter  of  the  trunk:  in  this  "respect  they  differ  very  materially 
from  the  os  femoris,  which  not  only  inclines  forwards  in  its  de- 
scent, but  also  leans  towards  its  fellow  internally,  and  almost 
touches  it  at  the  knee.  This  relative  position  of  the  leg  and 
thigh  is  obtained  by  the  greater  length  of  the  internal  condyle  of 
the  os  femoris,  and  also  by  the  other  peculiarities  of  form  in  the 
latter;  \\hereas  the  tibia  is  nearly  straight  in  the  direction  of  its 
long  diameter,  and  has  a  horizontal  articular  surface  above, 
whereby  it  and  the  os  femoris  make  an  entering  angle  externally 
and  a  salient  one  internally.  Under  common  circumstances,  the 


MECHANISM  OP  THE  INFERIOR  EXTREMITIES.  237 

weight  of  the  trunk  is  transmitted  to  the  foot  exclusively  through 
the  tibia,  owing  to^the  fibula  not  entering  into  the  composition  of 
the  knee  joint,  and  not  being  sustained  by  any  bony  basement  at 
its  inferior  part.  The  fibula  is  principally  intended  for  the  origin 
of  muscles,  and  for  the  lateral  security  of  the  ankle  joint ;  and 
may  be  broken  without  the'accident  suspending  either  erection 
or  locomotion. 

The  position  and  shape  of  the  foot  concur  largely  in  the  gene- 
ral object  of  maintaining  the  human  being  in  the  erect  attitude. 
Fixed  at  right  angles  to  the  leg,  and  articulated  by  a  surface  in 
the  centre  of  its  most  solid  structure,  the  tarsus,  it  receives  the 
weight  of  the  body  perpendicularly  upon  the  astragalus.  The 
latter  being  the  key-stone  .to  the  arch,  diffuses  the  pressure 
through  the  remainder  of  the  structure,  so  that  the  whole  foot  is 
planted  against  the  ground,  an  attitude  more  fully  executed  by 
man  than  by  any  other  animal.  The  tendency  of  the  body  to 
fall  forwards,  requires  a  very  considerable  elongation  of  the  foot 
in  front  of  the  tarsus,  in  order  to  increase  the  extent  of  the  base 
of  support  in  that  direction,  We  accordingly  find  the  metatarsal 
bones  not  only  forming  bases  for  the  flexion  of  the  phalanges;  but 
also  by  their  great  length,  by  the  flatness  of  the  articular  faces 
which  they  present  to  the  tarsus,  and  by  their  consequent  im- 
mobility at  these  points,  extending  and  securing  the  base  of  the 
body  in  that  direction  to  which  its  gravitation  most  inclines 
it.  The  first  metatarsal  bone,  though  corresponding  in  place 
with  the  first  metacarpal,  is  very  unlike  it  in  other  respects. 
Of  predominating  magnitude,  but  parallel  with  the  other  bones 
and  immoveable  at  its  base,  it  is  obviously  intended  for  sustain- 
ing the  body,  and  least  of  all  for  prehension  and  for  antago- 
nizing the  other  bones,  as  is  the  case  with  the  thumb. 

The  points  on  which  the  foot  is  particularly  pressed  when  we 
stand,  are  the  tuberosity  of  the  os  calcis,  the  tuber  of  the  base 
of  the  last  metatarsal  bone,  with  the  under  surface  of  the  cuboi- 
des,  and  the  anterior  extremity  of  the  first  metatarsal  bone. 
The  arch  of  the  foot,  upon  which  this  depends,  may  be  considered 
in  two  ways:  one  is  in  the  longitudinal  direction,  and  has  its  abut- 
ments in  the  os  calcis  behind,  and  in  the  ends  of  the  metatarsal 
bones  in  front,  the  other  is  transverse,  is  but  slightly  elevated 


238  SKELETON. 

externally,  indeed  almost  flat,  while  it  is  raised  to  a  considerable 
height  internally.  This  double  arrangement  is  eminently  ser- 
viceable in  many  respects :  it  permits  a  concavity  in  which  the 
muscles  of  the  toes  may  repose  and  act  without  being  pressed 
upon  by  the  superincumbent  weight  of  the  body — it  also  per- 
mits a  free  flow  of  blood  and  of  nervous  energy  to  this  struc- 
ture, gives  a  very  elastic  base  to  the  whole  body,  and  allows 
itself  to  be  applied  to  such  inequalities  of  surface  as  it  meets 
with. 

It  has  been  agitated,  by  some  ingenious  inquirers  into  the 
original  condition  of  man,  whether  the  erect  attitude  is  natural 
to  him  and  not  the  result  of  an  advancement  in  civilization. 
Independently  of  the  proofs  derived  from  the  authentic  reports 
of  travellers  concerning  the  varieties  of  the  human  family,  from 
none  of  whom  have  we  rea'son  to  believe  that  the  latter  have 
any  where  been  found  adopting  habitually  the  attitude  of  quad- 
rupeds ;  there  are  evidences  derived  from  the  general  mechan- 
ism of  the  skeleton,  still  more  conclusive,  that  standing  is  fully 
natural  to  us.  For  example,  1st,  The  position  of  the  foramen 
magnum  occipitis,  evidently  farther  forwards  in  man  than  in 
animals,  indicates  that  his  voluminous  head  is  to  be  kept  in  equi- 
librium by  a  vertical  line  of  support  near  the  centre  of  its  base. 
2d.  The  ligamentum  nuchae,  weak  in  man,  is  strong  in  quadru- 
peds. 3d.  The  curvatures  of  the  spine  are  so  varied  as  to  di- 
minish the  tendency  to  fall  forward  when  we  are  erect.  4th. 
The  direction  of  the  orbits  of  the  eyes,  which  looking  for- 
wards, when  we  stand,  and  enabling  the  eye  to  apply  itself  to 
a  vast  circumference,  would,  in  the  quadruped  position,  be  di- 
rected towards  the  ground,  and  thereby  have  the  sphere  of  ob- 
servation reduced  to  a  few  yards.  5th.  The  opening  of  the 
nostrils,  when  we  stand,  permits  odours  to  ascend  easily  into 
the  nose ;  in  the  other  attitude  this  opening  would  be  directed 
backwards.  Such  are  the  circumstances,  in  connexion  with 
the  head  only,  which  indicate  the  necessity  of  the  biped  posi- 
tion for  the  full  enjoyment  of  the  functions  which  the  Creator 
has  given  to  us.  But  there  are,  also,  others  equally  evident 
in  the  mechanism  of  the  extremities,  and  of  the  parts  of  the 
trunk  to  which  they  are  attached.  Thus,  1st,  The  breadth  of 
the  pelvis,  and  the  slight  obliquity  of  its  superior  strait,  in  re- 


MECHANISM  OF  THE  INFERIOR  EXTREMITIES.  239 

gard  to  the  spine,  prevents  us  from  falling  to  one  side,  and,  at 
the  same  time,  brings  the  lower  extremities  immediately  in  a 
line  with  the  spine.  2d.  The  length  of  the  neck  of  the  os  fe- 
moris,  and  the  size  of  its  condyles.  3.  The  articulation  of  the 
knee,  which  permits  the  leg  to  be  brought  into  a  line  with  the 
os  femoris,  a  position  impracticable  in  quadrupeds.  4th.  The 
foot  being  articulated  at  a  right  angle  with  the  leg,  and  having 
its  tarsus  and  metatarsus  so  well  developed.  5th.  The  predo- 
minance of  the  transverse  diameter  of  the  thorax  over  the  ver- 
tical, which,  with  the  great  length  of  the  clavicle,  and  the 
shape  of  the  scapula,  unfit  the  latter  for  assisting  much  in  pro- 
gression. 6th.  The  shape  of  the  hand,  calculated  to  seize  upon 
objects,  but  from  the  length  of  its  phalanges  not  suited  to  sus- 
tain the  body.  7th.  The  mode  of  articulation  at  the  wrist, 
which,  from  its  mobility  and  weakness  in  the  direction  to  which 
the  weight  of  the  body  would  be  applied  to  it,  could  not  be 
brought  to  support  it  advantageously.  And,  lastly,  the  great 
disproportion  of  length,  in  the  adult,  between  the  upper  and 
lower  extremities,  when  an  attempt  is  made  to  walk  like  the 
quadruped. 

In  considering  the  skeleton  of  the  very  young  child,  it  is 
worthy  of  remark  how  closely  its  mechanism,  with  the  excep- 
tion of  the  head,  corresponds  with  the  habits  of  early  life. 
A  spine,  nearly  straight,  and  a  pelvis,  the  lateral  diameter 
of  whose  cavity  is  so  small  that  the  transverse  base  of 
support  is  much  diminished,  render  erection  inconvenient. 
LowTer  extremities  shorter  in  proportion  than  the  upper  ones, 
having  thigh  bones  nearly  straight;  also,  the  articulations 
of  the  knee  not  admitting  of  a  full  extension  of  the  leg. 
All  these  circumstances  prove  that  the  quadruped  position, 
inconvenient  and  intolerably  irksome  when  continued  for  a 
length  of  time  in  the  adult,  is  natural  to  the  young  infant. 

The  space  between  the  ossa  femorum, produced  by  the  breadth 
of  the  pelvis  and  the  length  of  their  necks,  and,  therefore,  always 
considerable  above,  varies  below  in  different  individuals.  A  cer- 
tain distance  at  the  latter  point  seems  to  be  indispensable  to  con- 
venient and  graceful  progression.  Thus,  when  it  is  in  excess,  it 
produces  the  deformity  called  bandy  legs,  and  causes  a  totter- 


240  SKELETON. 

ing  gait,  such  as  may  be  mimicked,  at  any  time,  by  walking 
with  the  legs  in  a  state  of  abduction:  but,  when  diminished,  it 
is  called  knocked  knees,  and  interferes  with  the  firmness  of  the 
step  by  causing  the  centre  of  gravity  to  pass,  alternately,  through 
the  internal  condyles  of  the  ossa  femorum,  instead  of  falling  ex- 
actly between  them. 

The  firmest  position  in  which  we  can  stand  is  that  in  which 
the  feet  are  perfectly  straight  and  parallel  with  each  other,  so  as 
to  form  a  square  base  for  the  support  of  the  trunk.  If  from  this 
position  the  toes  be  turned  either  inwards  or  outwards,  the  con- 
sequent reduction  of  the  antero-posterior  diameter  of  the  base, 
causes'  less  resistance  to  the  natural  inclination  of  the  trunk  for- 
wards. Whatever  may  be  the  grace  and  the  ultimate  intention 
of  the  first  position  in  dancing,  to  wit,  that  of  having  the  feet 
nearly  in  the  same  line,  with  the  heels  touching  and  the  toes  out- 
wards, it  is  certainly  the  most  unfavourable  attitude  for  ease  in 
keeping  the  body  erect  that  can  be  adopted;  for  the  base  of  sup- 
port being  diminished,  both  by  the  length  of  the  body  of  the  os 
calcis,  and  by  that  of  the  foot,  anterior  to  the  ankle  joint,  the 
trunk  is  continually  inclining  either  forwards  or  backwards,  and 
is  prevented  from  falling  only  by  the  alternate  action  of  the 
muscles  behind  and  in  front. 

When  we  are  upon  the  knees,  the  base  of  support  for  the 
trunk  being  entirely  withdrawn  in  front,  it  is  necessary,  in  order 
to  maintain  the  position,  and  to  prevent  falling  forwards,  that 
the  hip  joint  be  flexed  so  as  to  throw  the  weight  of  the  body  en- 
tirely behind  the  thigh  bones.  The  position  is  one  of  so  much 
restraint  and  fatigue  upon  the  muscles,  that  it  can  be  maintained 
for  a  long  time,  only  by  some  artificial  support  in  front,  or  by 
the  buttocks  falling  down  upon  the  legs,  and  resting  against  them. 

The  position  we  assume  on  being  seated  in  a  chair,  is  the 
easiest  of  any  of  those  in  which  the  trunk  is  kept  erect,  or  nearly 
so.  The  length  of  the  lever,  represented  by  the  whols  length  of 
the  skeleton,  is  then  diminished  one-half;  consequently,  any  pre- 
ponderance of  it  at  particular  points,  above,  bears  with  less  force 
upon  the  base.  The  base  itself  is  much  augmented  by  the  ampli- 
tude of  the  buttocks,  and  by  the  horizontal  position  of  the  thigh 


MECHANISM  OP  THE  INFERIOR  EXTREMITIES.  241 

bones  in  front;  and  may  be  also  increased,  at  pleasure,  by  the 
extension  of  the  legs.  If,  under  such  circumstances,  the  trunk 
of  the  body  be  slightly  advanced,  its  equilibrium  is  so  easily  main- 
tained as  to  require  but  a  very  little  muscular  action  to  continue 
it.  The  most  exposed  part  of  the  base  is  backwards;  and,  if  the 
trunk  be  kept  perfectly  erect,  there  is  some  tendency  of  it  to  fall 
in  that  direction.  Hence,  the  utility  of  backs  to  seats,  and  the 
fatigue  from  such  as  have  not. 


SECT.  VI. ON  THE  MECHANISM  OF  THE  INFERIOR  EXTREMITIES  IN 

REGARD  TO  LOCOMOTION. 


1.  Of  the  Motions  of  the  Thigh. 

These,  like  the  motions  of  the  os  humeri,  upon  the  scapula? 
consist  in  extension,  flexion,  abduction,  adduction,  rotation,  and 
circumduction;  but,  in  consequence  of  being  performed  upon  an 
immoveable  basis,  the  acetabulum,  they  are  much  less  extensive. 
In  order  that  they  may  be  understood  well,  it  will  be  useful  to 
assume  certain  points  of  reference  in  the  os  innominatum  and 
femoris.  These  are  the  trochanter  major,  the  pubes,  and  the 
anterior  superior  spinous  process  of  the  ilium.  In  standing;,  the 
lower  external  part  of  the  trochanter  major,  where  it  forms  a 
bulge  on  the  side  of  the  thigh  bone,  is  on  a  horizontal  line  with 
the  upper  part  of  the  symphysis  pubis.  A  triangle,  described  by 
lines  drawn  from  the  anterior  superior  spinous  process  to  the 
symphysis  pubis — from  the  latter  to  the  point  mentioned  of  the 
trochanter,  and  from  the  latter  to  the  anterior  superior  spinous 
process,  will  be  nearly  a  rectangle,  of  which  the  base  is  above, 
and  the  shortest  side  behind. 

The  flexion  of  the  os  femoris  is  that  motion  in  which  its  lower 
extremity  is  carried  forwards.  It  is  performed  with  great  ease 
and  freedom,  in  consequence  of  the  arrangement  of  the  articu- 
lar surfaces  of  the  bones,  and  of  the  capsular  ligament.  The 
head  revolves  freely  in  the  acetabulum,  the  ligamentum  teres 
is  put  into  a  slight  tension,  and  the  end  of  the  trochanter  major 

VOL.  I.— 21 


242  SKELETON. 

approaches  the  sciatic  notch.     The  extreme  point  of  this  mo- 
tion is  the  one  preserved  by  the  os  femoris  of  the  foetus  utero. 

Extension  is  the  reverse  of  flexion.  When  the  latter  has 
been  performed,  extension  restores  the  thigh  bone  to  its  verti- 
cal position,  and  carries  it  some  degrees  farther,  but  cannot  be 
executed  to  the  same  extent  behind,  that  flexion  is  in  front. 
When  pushed  to  an  extreme,  it  brings  the  trochanter  major 
under  the  inferior  anterior  spinous  process  of  the  ilium,  and  the 
round  ligament  is  put  very  much  upon  the  stretch;  it  is,  finally, 
arrested  by  the  lower  part  of  the  neck  of  the  os  femoris  lodging 
against  the  posterior  elevated  margin  of  the  acetabulum,  and 
by  the  thickened  part  of  the  capsule,  in  front  and  above,  being 
so  much  distended  as  not  to  yield  farther  without  laceration. 

Abduction  is  the  act  by  which  the  thigh  bones  are  separated. 
When  carried  to  an  extreme,  the  under  part  of  the  head  of  the 
os  femoris  leaves  the  acetabulum,  and  distends  very  forcibly 
the  capsular  ligament  at  this  point.  The  superior  fasciculus 
of  the  round  ligament  is  strongly  extended;  but  the  inferior 
fasciculus  is  kept  easy,  and,  indeed,  somewhat  relaxed.  This 
motion  is  arrested  by  the  trochanter  major  striking  against  the 
ilium;  without  which  it  would  be  much  more  extensive,  as  the 
capsular  ligament  is  strained  at  its  weakest  point,  and  relaxed 
at  the  strongest. 

Adduction  is  the  reverse  of  the  last.  The  muscles  which 
produce  it,  the  adductors,  from  their  situation  and  course,  are 
unable  to  give  an  extent  to  this  motion  much  beyond  the  act  of 
reinstating  the  thigh  when  it  has  been  abducted.  In  this  re- 
spect they  are  much  less  influential  than  the  great  pectoral 
muscle  which  adducts  the  os  humeri.  The  articular  sur- 
faces of  the  bones  are  suited  to  a  much  greater  latitude  of  this 
movement,  but  it  is  arrested  both  by  a  deficient  power  in  the 
muscles,  and  by  the  strong  upper  part  of  the  capsular  ligament 
being  put  upon  the  stretch. 

Circumduction  is  the  regular  succession  in  a  circle  of  the  four 
preceding  motions,  and  is  much  less  extensive  in  the  os  femoris 
than  in  the  os  humeri,  for  the  reasons  stated.  The  centre  of 
the  circle,  or  cone,  thus  described,  is  the  head  of  the  bone,  and 


MECHANISM  OF  THE  INFERIOR  EXTREMITIES.  243 

it  is  much  more  extensive  anteriorly  and  externally  than  pos- 
teriorly and  internally. 

Rotation,  owing  to  the  length  of  the  neck  of  the  os  femoris, 
is  extremely  well  marked,  and  is  indicated  by  the  trochanter 
major  moving  backwards  and  forwards.  The  radius  of  the 
circle  thus  described,  is  the  distance  between  the  centre  of  the 
head  of  the  os  femoris  and  the  bulging  external  part  of  the  tro- 
chanter major.  The  rotation  outwards  or  backwards  is  more 
fully  and  easily  performed  than  the  reverse,  owing  to  the  num- 
ber and  favourable  position  of  the  muscles  causing  it,  many  of 
which  are  specially  appropriated  to  its  production,  and  some 
others  partially  so.  This  movement  is  arrested  by  the  neck  of 
the  bone  striking  against  the  acetabulum  behind,  and  by  the 
tension  of  the  capsular  ligament  in  front.  Rotation,  forwards, 
having  but  few  muscles  to  produce  it,  and  they  neither  special- 
ly devoted  to  it,  nor  acting  very  advantageously  for  the  pur- 
pose, is  arrested  by  the  neck  of  the  bone  striking  against  the 
fore  part  of  the  acetabulum,  by  the  tension,  behind,  of  the  cap- 
sular ligament,  and  also,  by  that  of  the  ligamenturn  teres. 
When  the  convexity  and  the  neck  of  the  os  femoris  look  di- 
rectly forwards,  it  is  indicated  by  the  great  toe  pointing  in  the 
same  direction. 

2.  Of  the  Motions  of  the  Leg. 

The  movement  of  the  leg  upon  the  thigh  is  that  of  flexion, 
of  extension,  and  a  very  partial  degree  of  rotation. 

In  flexion,  the  head  of  the  tibia  slides  backwards  upon  the 
condyles  of  the  os  femoris,  which  are  prolonged  behind,  for  the 
purpose  of  extending  this  motion.  It  is  checked,  when  carried 
to  an  extreme,  by  the  posterior  margin  of  the  tibia  striking 
against  the  os  femoris,  and  by  the  tension  of  the  ligament  of 
the  patella.  In  the  mean  time,  the  lateral,  the  crucial,  and  the 
posterior  ligaments  are  relaxed.  The  patella,  always  station- 
ary, and  at  the  same  relative  distance  in  regard  to  the  head  of 
the  tibia,  slides  downwards  upon  the  trochlea  of  the  os  femo- 
ris, and  in  the  flexed  position  sinks  between  the  condyles,  so  as 
to  come  in  contact  with  the  ligamentum  mucosum. 


244  SKELETON. 

In  extension,  the  patella  rises  upon  the  condyles,  and  becomes 
prominent;  the  lateral  ligaments  are  rendered  somewhat  tense, 
and  the  motion  is  finally  checked,  by  the  resistance  of  the  cru- 
cial and  of  the  posterior  ligaments  of  the  articulation. 

The  rotation  of  the  bones  of  the  leg  can  only  be  performed 
when  they  are  flexed,  and  the  ligaments,  generally,  thereby  re- 
laxed, in  which  position  a  very  limited  motion,  inwards  and 
outwards,  is  perceptible.  The  motion,  outwards,  is  the  more 
extensive  of  the  two,  in  consequence  of  the  arrangement  of  the 
crucial  ligaments,  which  are  separated  from  each  other  by  it. 
The  motion,  inwards,  is  limited  by  these  ligaments  being 
brought  immediately  by  it  into  close  and  resisting  contact  with 
each  other.  In  either  case,  however,  the  posterior  and  the  la- 
teral ligaments  all  contribute,  ultimately,  to  arrest  the  motion. 

In  all  these  conditions  of  the  leg,  the  semi-lunar  cartilages 
slide  somewhat  upon  the  head  of  the  tibia. 

The  articulation  between  the  tibia  and  the  fibula  is  such  as 
to  admit  of  no  motion  whatever  below;  but,  above,  a  limited 
sliding  backwards  and  forwards  is  performed  by  the  fibula 
upon  the  tibia.  This  movement  is  made  more  perceptible  in 
cases  of  extreme  emaciation,  and  in  general  relaxation  of  the 
muscular  system. 

3.  Of  the  Motions  of  the  Foot. 

The  general  motions  of  the  foot  upon  the  bones  of  the  leg 
are  flexion,  extension,  and  an  inconsiderable  inclination  inwards 
and  outwards. 

In  flexion,  the  astragalus  rolls  backwards  in  the  articular 
cavity  formed  by  the  tibia  and  the  fibula,  and  is  arrested  by  the 
anterior  upper  part  of  the  astragalus  coming  in  contact  with 
the  articular  margin  of  the  tibia.  The  ligamentous  fibres  and 
the  synovial  membrane,  in  front  of  the  articulation,  are  re- 
laxed; those  behind  are  in  a  state  of  tension,  as  well  as  the 
tendo-achillis,  and  the  other  tendons  there.  Luxation  from  an 
excess  of  this  motion  is  impossible. 


MECHANISM  OF  THE  INFERIOR  EXTREMITIES.  245 

In  extension,  the  foot  is  brought  with  the  point  downwards, 
so  as  to  have  its  upper  surface  almost  on  a  line  with  the  bones 
of  the  leg.  The  astragalus  glides  forwards;  the  tendons,  on  the 
back  of  the  joint,  are  very  much  relaxed.  The  joint  itself  is  in 
a  state  the  reverse  of  the  preceding. 

In  the  lateral  motions,  the  sole  of  the  foot  is  caused  to  pre- 
sent itself  either  obliquely  inwards  or  outwards,  whereby  it 
may  be  accommodated  to  any  inclined  surface  on  which  we 
walk.  The  first  position  is  checked  by  the  internal  malleolus, 
and  the  tension  of  the  external  lateral  ligaments;  the  second, 
by  the  external  malleolus,  and  by  the  tension  of  the  internal 
lateral  ligament.  These  motions  constitute  the  adduction  and 
the  abduction  of  the  foot;  and  by  a  regular  succession  with  its 
flexion  and  extension,  communicate  a  very  limited  and  embar- 
rassed species  of  circumduction. 

The  bones  of  the  tarsus,  for  the  most  part,  have  a  very  ob- 
scure motion  upon  each  other,  with  the  exception  of  the  arti- 
culation between  the  astragalus  and  the  scaphoides,  and  be- 
tween the  os  calcis  and  cuboides.  At  these  points  the  move- 
ment upwards  and  downwards,  makes  a  sort  of  flexion  and 
extension  of  the  fore  part  of  the  foot,  which  is  very  distinct. 
A  species  of  twisting,  or  oblique  gliding,  is  also  slightly  percep- 
tible there. 

The  bones  of  the  metatarsus  are  susceptible  of  a  slight  eleva- 
tion and  depression,  which,  almost  imperceptible  at  their  bases, 
become  sufficiently  obvious  at  their  anterior  extremities.  They 
also  may  be  slightly  approximated,  at  their  fore  parts,  by  the 
action  of  muscles,  and  by  external  compression.  When  the 
weight  of  the  body  is  thrown  upon  them,  they  separate  from 
each  other,  and  the  metatarsus  loses,  in  some  degree,  the  arched 
form  of  its  anterior  extremity  below. 

The  phalanges  of  the  toes  have  the  same  motions  with  those 
of  the  fingers,  except  that  they  are  more  restricted.  The  first 
ones,  therefore,  perform  flexion,  extension,  adduction,  abduction, 
and  circumdaction ;  the  last  two  have  only  flexion  and  exten- 
sion. The  extension  of  the  first  phalanges  is  more  extensive 

21* 


246  SKELETON. 

than  their  flexion,  from  whence  results  an  important  advantage 
in  walking  or  in  standing  upon  the  toes.  The  shortness  of  the 
second  and  third  phalanges  of  the  small  toes,  together  with  the 
thickness  of  the  sole  of  the  foot  contiguous  to  them  in  their  ex- 
treme flexion,  causes  them  rather  to  be  doubled  up  on  them- 
selves, than  on  the  sole  of  the  foot. 


On  the  General  Motions  of  the  Lower  Extremities. 

These  may  be  resolved  into  three;  walking,  running,  and 
leaping. 

In  walking,  though  the  first  step  may  be  taken  in  a  variety 
of  relative  positions  of  the  lower  extremities  to  each  other,  yet 
it  will  make  the  investigation  more  clear  to  suppose  the  indivi- 
dual standing  erect,  with  the  two  feet  precisely  on  the  same 
plane,  and  giving  equal  support  to  the  trunk.  The  first  step  is 
then  taken,  by  detaching  the  foot  of  one  side  from  the  ground ; 
in  order  to  do  which,  the  thigh  is  bent  upon  the  trunk,  the  leg 
upon  the  thigh,  and  the  limb  by  being  thus  elevated  becomes 
shorter.  At  this  period  the  ankle  joint  remains  at  rest,  with  a 
slight  inclination  of  the  toes  downwards.  By  the  subsequent 
relaxation  of  the  muscles  of  the  limb  advanced,  with  an  incli- 
nation of  the  trunk  to  the  same  side,  the  limb  is  caused  to  de- 
scend upon  the  ground.  These  are  the  only  motions  when  the 
step  is  short  and  easy;  but,  when  a  long  stride  is  taken,  by  which 
the  limb  is  put  very  much  in  advance  of  its  fellow,  in  order  to 
bring  it  to  the  ground,  the  pelvis  is  caused  to  rotate  forwards 
on  the  head  of  the  stationary  thigh  bone,  whereby  the  trunk  of 
the  body,  instead  of  presenting  the  sternum  forwards,  has  it 
turned  to  one  side. 

When  a  step  has  been  taken  so  as  to  leave  one  inferior  extre- 
mity advanced  before  the  other,  for  example  the  left,  the  limb 
behind  is  brought  forward  by  .the  following  mechanism: — The 
left  foot,  remaining  fixed,  becomes  the  point  of  support  to  the 
trunk;  and  the  right,  which  is  behind,  is  elevated  successively, 
from  the  heel  to  the  toes,  by  the  action  of  the  muscles  on  the  back 
of  the  leg,  and  rests,  upon  the  phalanges.  The  effect  of  this  po- 
sition is  to  elongate  the  right  inferior  extremity  to  the  amount 
of  the  distance  between  the  fore  part  of  the  ankle  joint  and  the 


MECHANISM  OF  THE  INFERIOR  EXTREMITIES.  247 

anterior  extremity  of  the  metatarsus,  whereby  that  side  of  the 
pelvis  is  pushed  forwards,  and  a  rotation  in  advance  impressed 
upon  it.  By  the  latter  impulse,  the  foot  of  that  side  is  wholly 
detached  from  the  ground,  the  thigh  being  flexed  at  the  same 
moment  at  the  hip  joint,  and  the  leg  flexed  at  the  knee,  the 
whole  extremity  is  carried  forward  and  fixed  upon  the  ground, 
after  the  manner  described  in  the  first  step.  Ordinary  progres- 
sion results,  then,  from  the  regular  succession  of  the  last  mo- 
tion in  the  two  extremities.  In  regard  to  the  impulsion  of  the 
pelvis  from  the  foot  behind,  this  will  probably  take  place  in 
every  case,  more  or  less;  it  may  however,  be  reduced  very 
much  by  a  certain  extent  of  flexion  at  the  knee  joint;  and  the 
want  of  it  not  be  felt,  because  other  powers  concur  to  produce 
the  same  impulsion;  as  certain  muscles,  and  also  the  momen- 
tum of  swinging  the  lower  extremity  forward. 

An  equality  of  length  in  the  lower  extremities  is  indispensa- 
ble to  graceful  and  regular  progression.  If  one  of  them  be 
shortened  from  any  cause  whatever,  it  is  manifested  in  the  gait, 
by  an  unusual  sinking  of  the  pelvis  on  the  defective  side,  at  the 
moment  the  foot  is  brought  to  the  ground,  and  from  the  conti- 
nuity of  the  pelvis  with  the  upper  parts  of  the  body,  a  conside- 
rable lateral  inclination  is  communicated  to  the  latter  in  the 
same  instant.  The  pains  frequently  taken  to  conceal  this  de- 
fect, disguise  it  very  imperfectly,  unless  the  shortness  be  only 
such  as  may  be  supplied  by  a  shoe  with  a  sole  thicker  than 
that  of  the  other  foot.  Where  the  shortness  arises  from  luxa- 
tion upwards  of  the  os  femoris,  a  crutch  is  the  best  substitute 
for  sustaining  that  side  of  the  pelvis. 

In  running,  the  position  of  the  feet  is  somewhat  different  from 
what  it  is  in  walking;  they  are  extended  so  as  to  support  the 
trunk  on  the  phalanges  alone,  instead  of  on  their  soles:  whereby 
a  double  advantage  is  obtained,  that  of  keeping  the  lower  extre- 
mities at  their  greatest  possible  length,  and  also  of  enabling  them 
to  detach  themselves  quickly  from  the  ground.  The  velocity 
here  is  the  principal  difference  between  it  and  walking,  yet  there 
are  some  peculiarities. 

The  trunk  of  the  body  is  kept  continually  and  largely  inclined 
forwards,  which  enjoins  the  necessity  of  a  quick  successive  ad- 
vance of  the  lower  extremities  to  prevent  it  from  falling.  This 


248  SKELETON. 

position,  also,  by  advancing  the  bony  points,  from  which  arise 
several  of  the  muscles  used  in  the  extension  of  the  thigh,  removes 
these  muscles  more  from  the  line  of  their  contraction,  and  there- 
by enables  them  to  act  more  advantageously  and  promptly.  As 
each  pace  on  these  occasions  is  taken  to  the  fullest  stretch,  the 
pelvis  is  rotated  forwards  from  side  to  side,  alternately  upon  the 
head  of  the  os  femoris,  which  may  be  fixed  at  the  time.  The 
face  being  directed  forwards,  whatever  rotation  in  the  vertebrae 
can  occur,  is  then  performed.  As  the  pelvis  communicates  its 
motions  to  the  trunk,  so  the  latter  carries  its  own  to  the  upper 
extremities;  which  are  thereby  slung,  alternately,  backwards 
and  forwards,  and  are  brought,  continually,  to  adjust  the  centre 
of  gravity,  which  is  then  more  in  danger  of  being  lost  than  in 
ordinary  walking. 

The  ascent  of  an  inclined  plane,  either  by  walking  or  running, 
is  attended  with  unusual  fatigue  and  difficulty,  for  the  following 
reasons:  In  order  to  advance  the  thigh,  it  is  necessary  to  give  it 
great  flexion  at  the  hip  joint,  the  knee  must  also  be  bent  in  an 
equal  degree,  and  the  foot  be  flexed,  in  order  to  adjust  it  to  the 
surface  against  which  it  reposes.  To  bring  forward  the  other 
extremity,  it  requires  an  equal  flexion  at  the  hip  and  knee;  be- 
sides which,  its  heel  being  below  the  phalanges,  the  foot  must 
perform  a  full  rotation  at  the  ankle  joint.  The  difficulty  is 
somewhat  diminished  by  stepping  only  on  the  phalanges.  As,  in 
these  cases,  the  trunk  of  the  body,  to  preserve  its  equilibrium, 
must  be  inclined  forwards,  there  are  certain  acclivities,  which, 
though  they  furnish  a  base  sufficiently  large  for  the  foot,  are 
yet  impracticable  from  not  allowing  the  trunk  to  be  thrown  for- 
wards. 

The  descent  of  an  inclined  plane  is  more  easy,  because  it  re- 
quires but  little  flexion,  in  the  articulations  mentioned,  to  bring 
the  extremity  behind  on  a  line  with  that  in  front;  and  its  subse- 
quent descent  is  produced  by  keeping  it  almost  straight,  and 
shortening  the  extremity  which  is  fixed.  Running  is  then  at- 
tended with  some  inconveniences,  for  the  impulsion,  forwards, 
which  this  motion  communicates  to  the  trunk,  assisted  by  the  in- 
clination of  the  plane  in  that  direction,  determines  a  fall,  inevita- 
bly, without  a  successively  accelerated  advance  of  the  hind  leg. 
We  see  frequently,  in  the  descent  of  a  very  inclined  hill,  a  step, 
at  first  guarded  and  leisurely  taken,  converted,  unavoidably, 


MECHANISM  OF  THE  INFERIOR  EXTREMITIES.  249 

into  a  full  run,  to  prevent  the  body  from  being  precipitated  for- 
wards to  the  ground. 

In  jumping,  the  whole  body  is  projected  abruptly  from  the 
ground,  either  in  a  vertical  or  oblique  direction. 

In  the  first,  the  lower  extremities  are  shortened  by  a  general 
flexure  of  their  articulations,  and,  by  a  very  sudden  and  simul- 
taneous extension  of  them,  the  resistance  of  the  ground  causes 
the  whole  frame  to  mount  upwards,  till  its  gravitation  causes 
the  momentum  to  cease;  it  then  descends  on  the  same  principle 
with  projectiles,  generally.  In  the  oblique  leap,  there  is  the 
same  flexion  in  all  the  articulations  of  the, lower  extremities, 
with  the  addition  of  an  inclination,  forwards,  of  the  trunk.  At 
the  moment  when  the  limbs  straighten  themselves,  the  trunk  is 
projected,  not  only  upwards,  but  forwards,  owing  to  its  inclina- 
tion, and  describes  in  its  ascent  and  descent  a  parabola.  In  this 
effort,  the  space  traversed  will  be  more  considerable,  if  a  pre- 
vious horizontal  momentum  has  been  communicated  to  the  trunk 
by  running  several  steps  before  the  leap  be  made. 

The  more  oblique  the  leap  is,  the  greater  will  be  its  extent, 
to  effect  which  the  trunk  must  be  inclined  proportionably  for- 
wards. But,  to  obtain  this  inclination  without  falling,  it  is  ne- 
cessary for  one  of  the  lower  extremities  to  be  very  much  ad- 
vanced at  the  moment  of  springing  with  the  other,  so  as  to  con- 
vert the  motion  into  a  very  long  step.  With  this  position  of 
the  lower  extremities,  a  much  longer  space  can  be  cleared  than 
if  they  were  kept  together.* 

*  For  a  farther  exposition  of  the  principles  of  locomotion,  see  Joh.  Alph.  Bo- 
relli  de'Motu  Animalium,  1710.  Haller,  Element  Physiol.  torn.  iv.  1757.  Bi- 
chat,  Anat.  Descript.  1801.  Barthez,  Nouvelle  Mechanique  des  Movemens  de 
1'Homme  et  des  Animaux,  1798. 


BOOK  I. 


PART  III. 

CHAPTER  I. 

ARTICULATIONS. 
OF  THE  CARTILAGINOUS  SYSTEM. 

CARTILAGES  (Cartilagines,  Systkme  Cartilagineux,)  supply  the 
place  of  bone  in  many  parts  of  the  human  skeleton,  as  in  the 
space  between  the  ribs  and  sternum,  in  the  larynx,  in  the  ex- 
ternal ear,  in  the  nose,  and  elsewhere.  They  are  also  to  be 
found  in  all  the  moveable,  and  in  several  of  the  immoveable  ar- 
ticulations. Wherever  placed  they  may  be  recognised  by  their 
whiteness,  by  their  flexibility,  by  their  great  elasticity,  and  by 
a  hardness  only  short  of  that  of  the  bones.  There  are  many  ani- 
mals whose  skeletons  are  .entirely  cartilaginous,  as  the  chon- 
dropterous  or  cartilaginous  fishes,  so  excellent  a  substitute  is 
cartilage  for  bone. 

Cartilages  have  neither  canals  nor  cells  in  them.  They  appear 
homogeneous;  and,  upon  a  superficial  inspection,  present  neither 
laminas  nor  fibres.  The  immersion  of  them  in  boiling  water 
dissolves  into  a  jelly,  such  as  are  found  upon  the  articular  sur- 
faces of  the  bones,  and  a  few  others ;  but,  such  as  supply  the 
place  of  bone,  though  softened  by  the  process,  are  not  rendered 
by  any  means  so  gelatinous.  Their  chemical  analysis,  accord- 
ing to  Mr.  I.  Davy,  is  gelatine,  44.5;  water,  55.;  phosphate  of 
lime,  0.5.  The  testimony  of  different  experimenters,  upon  the 
latter  point,  does  not  coincide,  and  their  results  must  vary  ac- 
cording to  the  kind  of  cartilage,  and  the  period  of  life. 

Cartilages  are  composed  of  a  tissue  exclusively  their  own, 


252  SKELETON. 

and  of  parts  which  they  have  in  common  with  other  organs. 
The  first  has  some  very  distinguishing  properties.  It  resists 
putrefaction,  either  with  or  without  maceration,  longer  than  any 
other  tissue,  except  the  bones.  In  the  midst  of  gangrene  it  pre- 
serves its  appearance  almost  unchanged.  Boiling  gives  it  a  yel- 
low colour,  causes  it  to  swell,  and,  if  protracted,  the  gelatinous 
portion  is  dissolved.  When  dried,  it  becomes  of  a  semi-trans- 
parent yellow,  diminishes  Fn  bulk,  and  loses  its  elasticity ;  in 
these  respects  resembling  ligaments  and  tendons. 

Cellular  substance  exists,  in  very  small  quantities,  in  carti- 
lage, and  is  therefore,  not  readily  demonstrated;  it  is,  however, 
made  manifest  by  maceration,  and  by  the  action  of  boiling  wa- 
ter: the  latter,  by  dissolving  the  gelatinous  portion,  leaves  a 
membranous  and  cellular  structure.  It  is  also  stated,  that  in 
certain  diseases,  the  gelatinous  portion  being  less  abundantly 
secreted,  the  cellular  is  left  in  a  soft  spongy  condition. 

In  a  healthy  state,  no  blood  vessels  can  be  seen  in  cartilages; 
yet  there  are  the  strongest  proofs  of  a  species  of  circulation  go- 
ing on  in  them,  either  by  very  fine  capillary  vessels,  or  an  in- 
terstitial absorption.  All  experienced  anatomists  have  seen,  in 
subjects  affected  with  jaundice,  the  entire  cartilaginous  system 
losing  its  brilliant  whiteness,  and  becoming  of  a  light  yellow: 
also,  the  conversion  into  bone,  in  extreme  old  age,  to  which  all 
cartilages,  with  but  few,  perhaps  no  exceptions,  are  subject ;  and 
this  ossification  sometimes  beginning  in  the  centre  of  the  carti- 
lage, prove  that  the  calcareous  matter  has  been  conveyed  there 
by  some  kind  of  channel. 

Neither  absorbents  nor  nerves  have  been  traced  into  them, 
and  it  is  not  possible  to  prove  conclusively,  their  existence  by 
the  circumstances  of  disease.  We  only  know,  that  in  inflam- 
mations of  the  joints,  terminating  by  anchylosis,  the  cartilages 
are  absorbed ;  and  that  in  some  cases,  even  without  evident  in- 
flammation, the  cartilage  is  removed  from  a  joint  as  if  it  had 
been  worn  away.  Ulcerations  of  the  arytenoid  cartilages  are 
spoken  of  as  common,  by  the  French  anatomists;*  but  it  has 
not  occurred  to  me  to  see  either  them  or  any  others  in  this 
state :  the  late  Dr.  Physick's  experience  is  also  the  same  with 

*  I  have,  since  the  first  edition  of  this  work,  seen  several  instances  in  _chronic 
Laryngitis. 


DEVELOPMENT  OF   CARTILAGES.  253 

my  own.  Possessed  of  no  animal  sensibility  in  the  natural 
state,  it  is  doubtful  whether  they  ever  have  it,  or  can  inflame, 
as  the  pains  in  inflammations  of  the  joints  may  arise  from  the 
synovial  membranes. 

In  the  embryo,  the  osseous  and  cartilaginous  systems  are 
confounded,  so  as  to  present  a  homogeneous,  mucous  or  pulpy 
appearance;  they  only  become  distinct  by  the  deposite  of  cal- 
careous matter  in  the  bones:  when  the  latter. are  somewhat  ad- 
vanced, the  cartilages,  which  are  to  remain  such,  have  also 
additional  consistence,  and  more  of  a  proper  cartilaginous  look; 
but  the  appearance  is  generally  unsatisfactory,  by  which  one 
can  learn  to  distinguish  the  cartilages  that  are  to  remain  such, 
from  the  cartilaginous  rudiments  of  the  bones.  The  following 
circumstance,  however,  is  pointed  out  by  Bichat:  in  the  carti- 
lages of  ossification,  there  is  a  vascular  net-work  between  the 
cartilage  and  the  ossification  which  has  occurred,  and  owing 
to  the  interposition  of  it,  the  two  may  be  easily  separated. 
But,  in  the  permanent  cartilage,  this  net-work  does  not  exist 
between  the  proximate  surfaces,  consequently  they  adhere 
with  a  tenacity  not  admitting  of  a  rigid  separation  from  one 
another. 

As  the  individual  reaches  adult  age,  the  cartilages  acquire 
the  strength,  whiteness,  and  great  elasticity  which  distinguish 
them.  In  old  age  they  become  yellowish,  more  brittle,  and 
are,  as  said,  generally  disposed  to  ossify.  Those  of  the  ribs 
and  larynx  are  frequently  ossified  at  forty  years  of  age.  The 
ossification  of  those  of  the  moveable  joints  is  rare,  and  begins 
at  a  more  advanced  period.  In  the  first  two  it  begins  com- 
monly near  their  centre,  and  in  the  last  on  the  surface. 


ACCIDENTAL  DEVELOPMENT  OF  CARTILAGES. 

The  unnatural  development  of  cartilages,  in  the  tissues  and 
organs  of  the  body,  to  which  they  are  very  slightly  allied  in 
their  nature,  is  a  circumstance  by  no  means  uncommon,  and 
is  met  with  annually,  in  most  of  its  varieties,  in  our  dissecting- 
rooms.  As  there  is  a  great  disposition  in  such  cartilages  to 
ossify,  they  are  presented  in  the  several  gradations  from  a  soft 
gelatinous  body  to  that  of  perfect  bone.  They  occur  in  the 

VOL.  L— 22 


254  SKELETON. 

articulations;  in  the  lungs,  and  form  there  fistulous  passages; 
very  frequently  on  the  surface  of  the  spleen;  in  the  pleura;  in 
the  fibrous  coat  of  the  large  arteries,  particularly  the  arch  of 
the  aorta;  and  in  the  semi-lunar  valves  of  the  same;  in  the  ova- 
rium,  when  it  becomes  dropsical;  and  also  in  many  other  parts 
of  the  body. 

The  cartilages  which  are  found  loose  in  the  joints  and  float- 
ing about  there,  begin,  for  the  most  part,  in  the  fibrous  struc- 
ture* exterior  to  the  synovial  membrane;  the  latter  is  protruded 
inwards  by  them,  and  gives  them  a  covering  resembling  the 
finger  of  a  glove.  As  these  bodies  are  small  and  rounded, 
when  they  protrude  into  the  joint  the  synovial  membrane  forms 
a  pedicle  or  base  to  them,  which  is  finally  ruptured,  and  then 
the  cartilage  becomes  loose.  These  bodies  are  generally  ossi- 
fied in  their  centre,  of  course  they  have  gone  through  the  usual 
progress  and  phenomena  of  ossification.  The  other  forms  of 
preternatural  cartilage  are  much  disposed  to  ossify  in  the  arte- 
ries, but  not  so  much  so  in  the  other  organs.  In  these  cases 
they  are  laminated  and  adhere  by  their  surfaces,  very  closely, 
to  the  contiguous  structure,  so  as  to  be  membranous.  M. 
Laennec  has  seen  a  cartilaginous  transformation  of  the  mucous 
membrane  of  the  urethra;  M.  Beclard  of  the  mucous  membrane 
in  the  vagina,  attended  with  prolapsus  uteri,  and  also  of  the 
prepuce  of  an  old  man  who  had  a  phyrnosis  from  birth. 

OF  THE  PERICHONDRIUM. 

All  the  cartilages,  except  the  articular  ones,  are  invested  by 
a  membrane  called  perichondrium,  (perichondre.)  It  is  best 
seen  on  the  larynx,  and  on  the  cartilages  of  the  ribs.  Its  struc- 
ture is  fibrous,  and  corresponds  so  fully  with  that  of  the  peri- 
osteum that  it  may  be  considered  the  same  sort  of  membrane. 
It  is,  however,  less  vascular  than  the  periosteum,  and  adheres 
to  the  cartilages  with  less  force,  owing  to  the  fibrous  connexion 
between  them  being  not  so  abundant.  Bichat's  experiments 
prove  that  the  cartilage  is  much  less  affected  by  the  loss  of  this 
membrane,  than  the  bone  is  by  that  of  the  periosteum:  its  uses 
are  no  doubt  the  same. 

*  Beclard,  Anat.  Gen. 


ARTICULAR  CARTILAGES.  255 


OF  THE  ARTICULAR  CARTILAGES. 

To  this  class  we  refer,  exclusively,  such  as  adhere  by  one 
surface  to  the  articular  facings  of  the  bones,  and  present  the 
other  surface  to  the  cavity  of  the  joint.  Every  moveable,  and 
some  of  the  immoveable  articulations,  have  their  surface  uni- 
formly thus  incrusted,  to  a  thickness  varying  from  the  fraction 
of  a  line  in  the  smallest  joints,  to  one  line  in  the  largest.  The 
cartilage  itself  is  rather  thinner  near  the  margin  of  the  articular 
surface,  when  the  latter  is  convex,  than  it  is  near  the  centre; 
on  the  contrary,  when  the  surface  is  concave,  the  cartilage  is 
thickest  near  its  periphery. 

These  cartilages,  when  subjected  to  a  maceration  of  six 
months,  are  stripped  of  the  reflection  of  synovial  membrane, 
which  covers  their  articular  surfaces,  and  are  resolved  into 
fibres,  one  end  of  which  adheres  to  the  bone  and  the  other  end 
points  to  the  joint.  If  the  preparation  be  then  dried,  the  dis- 
tinction of  fibres  becomes  more  manifest. 

The  most  successful  injections,  closely  examined  with  a  mi- 
croscope, demonstrate  the  defect  of  blood  vessels  in  them.  The 
vessels  are  uniformly  seen  to  terminate  at  the  circumference  of 
the  cartilage  and  at  the  face  which  adheres  to  the  bone,  but 
never  to  penetrate  it.  Their  organization  is,  therefore,  ex- 
tremely simple,  and  such  as  subjects  them  to  but  few  morbid 
alterations.  When  partially  removed  from  the  bone  the  latter 
occasionally  reproduces  them,  but  the  edges  of  the  new  and  of 
the  old  production  do  not  unite.  I  have,  in  cases  of  inflamma- 
tion of  the  joints,  seen  the  fibres  of  these  cartilages  much  longer 
than  usual  and  detached  from  each  other.  When  a  joint  is 
laid  open  by  a  wound,  and  suppurates,  the  cartilage  softens 
and  disappears  from  the  circumference  to  the  centre.* 

*  Bichat,  Anat.  Gen.  The  same  author  speaks  of  the  idiopathic  ulceration  of 
the  cartilage,  as  a  result  of  its  inflammation.  The  late  Dr.  Physick,  whose  ex- 
perience  is  equal,  denies  both. 


256  SKELETON. 


CHAPTER  II. 

OF  THE  FIBRO  OR  LIGAMENTO-CART1LAGINOUS  SYSTEM. 

THIS  set  of  organs  (Systeme  fibro-cartilagineux)  has  been 
placed  -by  anatomists,  indiscriminately  in  the  cartilaginous  or 
in  the  ligamentous  system,  in  consequence  of  its  participating 
in  the  characters  of  both;  it,  however,  from  its  importance, 
should  have  a  distinct  position.  There  are  three  varieties  of 
this  system.  The  first  presents  itself  in  a  membranous  state, 
and  is  represented  by  the  external  ear,  by  the  alas  of  the  nose, 
by  the  cartilage  of  the  eye-lids,  and  by  the  trachea.  The  se- 
cond is  represented  by  the  inter-articular  cartilages  of  the  move- 
able  articulations,  as  of  the  knee,  the  wrist,  lower  jaw,  and  also 
by  the  inter-vertebral  matter  which  holds  the  bodies  of  the  ver- 
tebrse  together.  And  the  third  is  represented  by  the  trochleas 
and  sheaths,  formed  on  the  surface  of  bones  for  the  gliding  of 
tendons. 

The  principal  constituent  of  this  system  is  a  strong  fibrous 
matter,  which  is  intermixed  with  the  cartilage,  and  has  in  some 
places  its  surface  covered  by  the  latter.  The  fibres  even  by 
superficial  observation  may  be  traced  in  various  directions:  in 
some  places  they  are  parallel;  in  others  intermixed  and  crossed 
very  much ;  in  others  concentric.  Their  strength  is  of  the  first 
degree.  The  cartilaginous  part  fills  up  the  intervals  between 
the  fibres,  and  gives  to  the  whole  structure  its  whiteness  and 
elasticity. 

The  Fibro-cartilages  may  be  converted  by  the  action  of  hot 
water  into  gelatine,  but  the  process  is  slower  than  in  the  sim- 
ple cartilage.  The  membranous,  or  first  variety,  differs  how- 
ever from  the  other  two  in  this  respect;  for  if  it  can  be  reduced 
at  all  into  gelatine,  the  quantity  it  yields  is  not  perceptible. 

This  system  is  destitute  of  perichondrium,  with  the  excep- 
tion of  the  first  variety,  in  which  it  is  distinguishable;  but  the 
others  either  adhere  to  the  bone,  or  are  covered  by  a  synovial 


LIGAlVfENTOUS  TISSUE.  257 

reflection;  their  margins  adhering  in  such  cases  to  the  conti- 
guous ligamentous  structure. 

There  is  a  very  small  quantity  of  cellular  tissue  in  this  sys- 
tem. Artificial  injection  manifests  but  few  blood  vessels  in  it; 
if  the  animal,  however,  be  strangled  for  the  purpose,  the  blood 
by  accumulating  in  the  capillaries  becomes  sufficiently  appa- 
rent. 


CHAPTER  III. 

OF  THE  LIGAMENTOUS  OR  DESMOID  TISSUE. 

SECT.  I. 

THE  Desmoid  Tissue,  (Textus  Desmosus,  Sys&me  Fibretix,) 
is  very  generally  diffused  in  the  human  body,  has  a  very  close 
connexion  with  the  cellular  texture,  and  is  continuous  with  it 
in  divers  places.  It  may  be  known  by  its  whiteness,  the  firm- 
ness and  unyielding  nature  of  its  materials,  and  its  fibrous  ar- 
rangement. It  is  most  commonly  employed  in  fastening  the 
bones  to  each  other  at  their  articulations,  and  in  enveloping 
the  muscles,  but  it  is  also  applied  in  many  other  ways.  Its  ap- 
plication in  the  former  is  our  present  object,  but  before  that  is 
particularly  noted,  it  will  be  useful  to  enter  into  some  general 
considerations  in  regard  to  its  intimate  structure,  and  the  ob- 
servations now  made  can  be  applied  on  all  other  occasions 
when  this  tissue  is  in  question. 

A  desire  to  generalize,  and  consequently  to  simplify,  has  in- 
duced anatomists  to  seek  for  some  fountain  or  source  from 
which  all  the  reflections  and  applications  of  the  desmoid  tissue 
might  be  traced.  The  Arabians  thought  that  the  dura  mater 
was  this  source;  and  the  error  was  sanctioned  for  a  long  time 
by  the  authority  of  Sylvius.  The  celebrated  Bichat,  in  ob. 
serving  the  connexions  of  this  tissue,  finding  that  all  its  points 
of  application  might  be  traced  either  mediately  or  directly  to 
the  periosteum,  considered  the  latter  as  its  centre,  as  the  heart 

22* 


258  SKELETON. 

is  the.  centre  of  the  circulation,  and  the  brain  of  nervous  ener- 
gy.; not  that  he  thought  the  periosteum  radiated  its  influence 
on  all  its  dependent  organs,  but  because  anatomical  inspection 
demonstrated  all  the  fibrous  organs  to  be  connected  with  it,  and 
communicating  through  it  with  each  other.  The  late  Profes- 
sor Bonn,  of  Amsterdam,  reversed  the  idea  of  Bichat,  and  con- 
sidered the  aponeuroses  of  the  extremities,  and  of  the  trunk, 
which  send  their  partitions  between  the  muscles,  and  down  to 
the  periosteum  and  joints,  as  the  much  desired  centre  of  the 
desmoid  system.  The  latter  idea  has  been  reiterated  by 
others,  and  the  supposed  emanations  from  the  superficial  apo- 
neurcses  diligently  traced.  As  means  of  studying  the  position 
and  connexions  of  parts,  notwithstanding  the  construction  is  a 
very  forced  one,  which  makes  desrnoid  tissue  cellular  mem- 
brane, and  cellular  membrane  desmoid  tissue,  alternately,  so 
as  to  suit  the  arrangement  of  the  anatomists,  instead  of  that  of 
nature;  yet,  any  or  all  of  these  plans  have  their  use,  and  may 
be  followed  advantageously,  after  the  study  at  large  of  the  hu- 
man fabric. 

The  desmoid  tissue  is  essentially  fibrous,  but  without  a  uni- 
form arrangement,  as  its  fibres  are  either  parallel,  crossed,  or 
mixed.  In  some  places  the  fibres  are  very  compact,  and  sepa- 
rate with  difficulty,  but  generally  prolonged  maceration  will 
cause  them  to  part  into  filaments  as  fine  as  the  thread  of  the 
silk-worm.  Anatomists  differ  in  regard  to  the  ultimate  struc- 
ture of  these  fibres.  By  M.  Chaussier  they  are  thought  to  be 
primitive  and  peculiar;  Mascagni*  supposed  that  they  were 
lymphatics  enclosed  in  a  vascular  web ;  Isenfiam,  that  they  were 
cellular  substance  imbued  with  gluten  and  albumen.  And  M. 
Beclard,  observing  that  maceration  resolves  them  into  a  spe- 
cies of  mucous  or  cellular  substance,  teaches  that  they  are  the 
latter  in  a  condensed  state.  Bichat's  opinion  is  probably  correct 
that  the  tissue  is  peculiar,  and  tha-t  maceration  only  brings  into 
view  the  cellular  substance  which  unites  its  fibres.  Though 
maceration  and  chemical  management  evolve  some  striking 
coincidences  with  cellular  membrane,  yet  in  the  natural  and 
ordinary  state  there  are  some  very  strong  points  of  difference 
from  it.  Among  these  may  be  remarked  its  great  want  of  elas- 

*  Prodrome  della  Grande  Anatomia. 


LIGAMENTOUS  TISSUE.  259 

ticity,  which  causes  it  to  tear  sooner  than  to  stretch ;  and  in 
general  anasarca,  its  being  only  very  partially  affected,  merely 
rendered  a  little  more  moist  and  tumid,  which  even  then  may 
arise  from  the  small  quantity  of  cellular  substance  in  it.  Many 
parts  of  it,  however,  are  unaffected  in  the  latter  way,  as  the 
tendons  and  their  sheaths.  This  tissue  naturally  contains  a 
considerable  quantity  of  water,  which  it  loses  by  exposure  to 
the  air;  it  then  is  much  reduced,  and  becomes  hard  and  yellow- 
ish, and  is  made  semi-transparent  by  being  put  into  spirits  of 
turpentine. 

The  desmoid  tissue,  by  being  subjected  to  the  heat  of  boiling 
water,  contracts,  becomes  more  solid,  and  is  elastic;  but  if  it  be 
continued  there,  it  gradually  softens,  becomes  semi-transparent, 
and  gelatinous.  The  mineral  acids  reduce  it  to  a  pulpy  state, 
and  if  concentrated,  will  dissolve  it  entirely.  The  alkalies  loosen 
its  texture,  cause  the  fibres  to  separate  easily,  and  to  assume  a 
diversity  of  colours.  It  putrefies  but  slowly,  in  this  respect  be- 
ing next  to  the  cartilages. 

The  strength  of  this  texture  is  remarkable,  and  adapts  it  to 
the  sustaining  of  enormous  weights;  a  faculty  which  is  conti- 
nually in  requisition,  both  to  retain  the  articular  surfaces  of 
bones  in  contact,  and  the  muscles  and  tendons  in  their  places. 
It  is  well  known  that  the  patella,  the  olecranon,  and  the  os  cal- 
cis,  break  frequently  before  their  tendinous  attachments  will 
give  way.  In  the  history  of  punishments,  where  criminals 
have  been  fastened  to  four  horses,  it  is  said  that  it  has  been  found 
necessary  to  use  a  knife  to  assist  in  their  disarticulation.  All 
these  phenomena  occur  when  abrupt  violence  is  resorted  to,  so 
little  are  the  ligaments  disposed  to  yield;  but  when  the  causes 
of  distention  act  slowly  and  gradually,  as  in  dropsies  of  the 
joints,  the  fibres  separate,  and  are  sometimes  completely  disu- 
nited. When  ihe  distending  cause  ceases  to  operate  in  the  lat- 
ter case,  the  ligaments  have  the  power  of  contracting  in  the 
same  gradual  way,  and  of  restoring  themselves. 

Some  of  the  desmoid  tissues,  besides  having  their  fibres  sur- 
rounded and  their  interstices  occupied  by  cellular  substance, 
contain  a  very  small  quantity  of  oily  or  fatty  matter.  This 
is  not  very  obvious  in  their  recent  state;  but,  by  drying  them, 
it  will  be  seen  in  small  quantities  on  their  surface,  like  a  greasy 
exudation:  this  probably  comes  from  the  cellular  substance  in 


260  SKELETON. 

them.  They  are  furnished  but  sparingly  with  blood  vessels, 
which  for  the  most  part,  are  capillary.  The  periosteum  and 
the  dura  mater  are,  however,  exceptions  to  this  rule.  Lym- 
phatic vessels  have  been  observed  in  some  of  them,  but  it  is 
doubtful  whether  they  generally  have  nerves.* 

The  sensibility  of  this  system  is  extremely  obscure,  and  is  not 
manifested  under  the  usual  mechanical  and  chemical  irritants; 
it  may,  however,  be  elicited  by  communicating  to  the  joints  a 
twisting  motion,  as  the  experiments  of  Bichat  prove.  Inflam- 
mation augments  their  sensibility,  in  which  case  it  becomes  ex- 
tremely acute,  as  in  gout  and  rheumatism,  or  any  other  cause 
productive  of  it. 


SECT.  II. OF  THE  LIGAMENTS  OF  THE  JOINTS. 

The  ligaments,  (ligamenta,)  properly  speaking,  are  those  or- 
gans which  tie  the  bones  together,  and  in  the  moveable  joints 
are  either  capsular  (capsules  jibreux)  or  funicular,  (ligamens 
jibreux  fasciculaires.)  The  first  are  like  a  bag  open  at  the 
ends,  at  either  of  which  the  articular  extremity  of  a  bone  is  in- 
cluded. These  are  much  more  complete  in  some  joints  than  in 
others;  the  shoulder  and  the  hip  joints  afford  the  most  perfect 
examples;  in  other  joints  they  are  divided  into  irregular  fasci- 
culi of  fibres,  permitting  the  synovial  membrane  to  appear  in 
their  interstices,  and  sometimes  they  are  still  more  widely  se- 
parated. 

The  funicular  ligaments  are  mere  cords,  extending  from  one 
bone  to  another;  some  of  them  are  flattened,  some  rounded,  and 
others  oval  or  cylindroid.  They  are  variously  placed ;  in  some 
instances  they  are  within  the  capsular  ligament,  and  in  others, 
on  its  outer  surface,  and  sometimes  so  blended  with  it  as  not  to 
be  separated  without  an  artificial  dissection.  Their  names  are 
derived  either  from  their  position  or  shape,  and  are  generally 
sufficiently  appropriate. 

*  Beclard,  Anat.  Gen. 


SYNOVIAL  ARTICULAR  CAPSULES.  261 


SECT.  III. OF  THE  SYNOVIAL  ARTICULAR  CAPSULES. 

Each  moveable  articulation  is  lined  by  a  membrane,  (Mem- 
brane Synoviale,}  reflected  over  the  internal  face  of  the  capsu- 
lar  ligament  and  the  articular  cartilages.  This  membrane  is 
a  perfect  sac;  and  unlike  the  capsular  ligament,  has  no  opening 
in  it.  It  is  remarkably  distinct  where  it  is  not  attached  to  the 
articular  cartilages;  and,  by  being  inflated,  is  caused  to  protrude 
in  small  vesicles,  or  pouches,  between  the  fasciculi  of  the  liga- 
mentous  structure.  Its  connexion  with  the  cartilage,  and  its 
continuation  over  it,  are  not  quite  so  obvious,  and  require  more 
management  to  demonstrate:  it  is,  indeed,  so  thin  and  transpa- 
rent at  this  part,  and  adheres  so-closely,  that  its  existence  there 
has  been  questioned,  but  may  be  proved  in  a  variety  of  ways. 
By  maceration  it  becomes  so  loose,  that,  with  a  pair  of  forceps, 
shreds  of  it  may  be  raised  along  the  whole  extent  of  the  carti- 
lage. If  a  flap  of  cartilage  be  raised  up  by  a  knife,  its  base 
being  left  attached,  in  attempting  to  tear  away  the  base  it  will 
be  found  that  the  synovial  membrane  is  continued  from  this 
base  to  the  contiguous  cartilage.  Saw  a  bone  through  to  its 
articular  cartilage,  then  tear  through  the  cartilage  gently,  in 
which  case  the  continuity  of  the  synovial  membrane  will  also 
be  manifested. 

From  these  several  proofs  the  fact  is  established,  that  the  sy- 
novial membranes  are  bags,  closed  at  both  extremities,  and  dif- 
fer thereby  from  the  capsular  ligaments. 

The  synovial  capsules  are  liable  to  a  fungous  degeneration 
which  occurs  equally  upon  the  cartilaginous  and  capsular  por- 
tions of  them.  Factitious  bridles  sometimes  form  in  the  joints, 
attached  indiscriminately  to  either  portion  of  the  synovial  mem- 
brane. M.  Beclard  says,  that  protracted  inflammation  will, 
finally,  redden  the  cartilaginous  portion,  and  that  it  extends  from 
the  circumference  to  the  centre,  the  hues  being  lighter  the 
nearer  it  is  to  the  latter.  It  has  not  occurred  to  me  to  meet 
with  this  proof;  though  I  have  made  frequent  dissections  in 
subjects,  of  inflamed  joints,  the  redness  has  always  ceased  at 
the  margin  of  the  articular  cartilage.  Dr.  Physick's  experience, 


262  SKELETON. 

most  valuable  on  all  occasions,  affords  support  to  my  own. — 
Some  years  ago  I  had  an  opportunity  of  investigating,  some- 
what fully,  this  point,  in  a  subject,  all  of  whose  large  joints  were 
in  a  state  of  inflammation. 

These  synovial  capsules,  or  membranes,  are  white,  thin,  se- 
mi-transparent, and  soft.  Wherever  there  is  a  deficiency  of 
capsular  ligament,  they  adhere  to  the  contiguous  cellular  sub- 
stance, and  are  so  blended  with  it  as  to  appear  absolutely  con- 
tinuous. Dissection,  inflation,  and  maceration,  prove  them  to  be 
laminated,  and  develop  their  structure  in  such  a  way  that  it  re- 
solves itself  into  a  cellular  tissue,  the  more  interior  layers  of 
which  had  been  in  a  very  compacted  state.  In  all  this  they  re- 
semble the  serous  membranes,  generally,  and  are  ranked  among 
them;  Bichat,  therefore,  considers  them  only  as  an  interlace- 
ment of  absorbents,  and  of  exhalents.  But,  for  the  farther  ex- 
position of  this  point,  see  the  article  on  the  Serous  Membranes. 

The  synovial  sacs  have,  on  their  outer  surface,  but  projecting 
into  the  cavity  of  the  joint,  adipose  cushions  of  different  sizes, 
called  the  Synovial  Glands  of  Havers,  from  which,  till  lately,  it 
was  supposed  that  the  lubricating  liquor  of  the  joints  is  exclu- 
sively secreted.  These  cushions  have  their  projecting  margins 
fringed  and  unusually  vascular,  and  occupy  the  small  spaces 
left  between  the  articular  faces  of  the  bones.  As  they  are  co- 
vered by  the  synovial  membrane,  they  no  doubt  assist  in  the 
secretion  of  the  synovia. 

The  moveable  articulations  are  all  furnished  with  the  fluid 
called  Synovia;  this  name  was  given  to  it  by  Paracelsus,  from 
its  resemblance  to  the  albuminous  part  of  an  egg,  to  the  con- 
sistence and  colour  of  which  it  has  a  close  affinity,  and,  like  it, 
is  thick,  ropy,  and  somewhat  yellowish.  The  chemical  analysis 
of  it  indicates  the  presence  of  water,  albumen,  and  a  kind  of  in- 
coagulable mucus.  It  was  once  supposed  to  be  a  mixture  of 
serum,  with  the  adipose  matter  of  the  bones,  which  found  its 
way  into  the  joints  by  transudation;  but  as  it  contains  upon  ex- 
periment no  oil,  the  opinion  is  evidently  erroneous.  It  is  se- 
creted from  the  whole  internal  surface  of  the  synovial  mem- 
brane, and,  perhaps,  in  greater  quantities  from  the  fringed  fatty 


ARTICULATION  OF  THE  LOWER  JAW.  263 

cushions  in  the  joints  in  consequence  of  their  increased  vascu- 
larity.  M.  Beclard  teaches,  that  it  is  neither  a  follicular  nor  a 
glandular  secretion,  nor  a  transudation,  but  a  perspiration,  in 
which  a  perfect  equilibrium  is  kept  up  between  its  exhalation 
and  its  absorption.  Its  use  is  to  diminish  friction,  and,  conse- 
quently, to  facilitate  the  sliding  of  the  bones  upon  each  other. 


CHAPTER    IV. 

ARTICULATION  OF  THE  LOWER  JAW. 

THE  articular  connexion,  here,  is  formed  by  that  portion  of  the 
glenoid  cavity  anterior  to  the  fissure,  and  by  the  condyle  of  the 
lower  jaw.  Each  surface  is  covered  by  thin  cartilage;  and  a 
thin,  loose,  irregular,  fibrous,  capsular  ligament,  arises  from  the 
articular  margin  of  one  bone,  to  be  inserted  into  that  of  the  other. 
Besides  this,  there  are  four  other  ligaments  for  strengthening 
the  joint,  an  inter-articular  cartilage,  and  two  synovial  mem- 
branes. 

The  External  Ligament  (Membrana  Articularis  Ligamen- 
tosa)  arises  from  the  inferior  margin  of  the  root  of  the  jugal  or 
zygomatic  process  of  the  temporal  bone,  and  from  the  anterior 
side  of  the  meatus  externus,  and  is  inserted  into  the  neck  of  the 
condyloid  process.  It  is  somewhat  triangular,  having  the  base 
upwards.  Just  in  advance  of  this,  and  separated  from  it  by  a 
small  fissure,  is  another  triangular  ligament,  the  discovery  of 
which  is  claimed  by  Caldani.*  It  arises  from  the  anterior  part 
of  the  inferior  margin  of  the  zygomatic  process  of  the  tempo- 
ral bone,  and  is  inserted  into  the  neck  of  the  bone  in  advance 
of  the  other. 

The  Internal  Ligament  (Lig.  Maxillce  Laterals)  arises  from 
the  extremity  of  the  spinous  process  of  the  sphenoid  bone,  and 
from  the  posterior  margin  of  the  glenoid  cavity,  that  is  the  pro- 
cessus  vaginalis,and  going  downwards  and  outwards,  is  inserted 

*  Tabul.  Anat.     Venetiis,  1802. 


264  SKELETON. 

into  the  spine  bordering  the  posterior  mental  foramen,  and  for 
some  distance  lower  down  on  the  ramus  of  the  jaw.  It  is  placed 
between  the  two  pterygoid  muscles,  and  is  in  contact  with 
the  maxillary  vessels  and  nerves,  as  they  run  between  it  and 
the  condyle  to  the  posterior  mental  foramen.  It  is  thought  by 
Caldani  to  be  not  so  useful  in  restricting  the  motion  of  the  jaw 
forwards,  as  in  holding  the  vessels  and  nerves,  and  regulating 
their  position,  lest  in  the  various  motions  of  the  lower  jaw 
they  should  be  displaced  and  injured. 

The  Stylo-maxillary  Ligament  is  thinner  than  the  above.  It 
arises  from  the  external  side  of  the  styloid  process,  and  is  in- 
serted into  the  posterior  margin  of  the  jaw,  near  its  angle,  be- 
tween the  masseter  and  internal  pterygoid  muscles.  The  sty- 
lo-glossus  muscle  is  much  connected  with  it,  and  is  thereby  as- 
sisted in  elevating  the  base  of  the  tongue,  the  fascia  profunda 
of  the  neck  is  in  continuation  with  it. 

There  are  two  synovial  membranes,  the  one  reflected  be- 
tween the  glenoid  cavity  and  the  upper  surface  of  the  inter- 
articular  cartilage,  and  the  other  between  this  latter  substance 
and  the  condyle  of  the  lower  jaw.  They  may  be  seen  at  differ- 
ent points  protruding  between  the  fibres  of  the  capsular  liga- 
ment. 

The  Inter-articular  cartilage,  by  being  placed  between  the 
two  synovial  membranes,  separates  completely  the  two  bones. 
Above,  its  surface  corresponds  to  the  convexity  of  the  tubercle 
of  the  temporal  bone,  and  to  the  glenoid  cavity;  below,  it  is 
simply  concave  for  receiving  the  condyle.  It  is  thicker  at  the 
circumference  than  in  its  middle,  and  at  the  posterior  than  the 
anterior  margin.  Sometimes  it  is  open  in  the  centre,  in  which 
case  the  two  synovia!  membranes  run  into  one  another.  Its 
structure  is  fibro-cartilaginous.  It  moves  very  readily  back- 
wards and  forwards. 

On  the  posterior  face  of  the  capsular  ligament,  I  have  found, 
in  several  cases,  indeed,  on  all  occasions  of  special  examination 
for  it,  since  the  first  observation,  an  erectile  tissue  or  structure 
resembling  the  corpus  cavernosum  penis.  It  has  not  been 


LIGAMENTS  OF  THE  SPINE.  265 

filled  with  blood  like  the  latter,  but  is,  probably,  an  arrange- 
ment for  giving  great  mobility  forwards  to  the  lower  jaw. 

The  movements  of  this  bone  may  be  simply  hinge-like,  by 
its  depression,  in  which  the  mouth  is  regularly  opened ;  or,  by 
the  action  of  the  pterygoid  muscles,  it  may  be  slid  forwards. 
When  the  muscles  of  but  one  side  act,  a  species  of  rotation  is 
communicated ;  in  which  one  condyle  advances  on  the  tubercle 
of  the  temporal  bone,  while  the  other  reaches  to  the  back  part 
of  the  glenoid  cavity.  The  looseness  and  length  of  the  capsu- 
lar  ligament  of  the  articulation,  along  with  the  extreme  facility 
of  motion  from  the  interposition  of  a  moveable  cartilage,  con- 
tribute very  materially  to  this  movement.  The  sliding  back- 
wards and  forwards  of  the  intermediate  cartilage  of  this  arti- 
culation, during  mastication,  sometimes  produces  a  cracking; 
audible  to  the  by-standers,  and  extremely  annoying  to  the  in- 
dividual who  is  the  subject  of  it,  from  the  noise  being  so  near 
his  ear. 

Some  persons  are  liable  to  a  spontaneous  dislocation  of  this 
bone,  from  yawning  too  widely.  I  am  disposed  to  believe,  that, 
in  such  cases,  the  accident  arises  from  the  posterior  boundary 
of  the  glenoid  cavity,  (as  established  by  that  margin  of  the 
temporal  bone  which  is  continuous  with  the  vaginal  process, 
and  forms  a  part  of  the  meatus  externus,)  being  more  advanced 
and  higher  than  usual;  in  consequence  of  which,  whenever  the 
bone  is  depressed  to  a  certain  point,  its  neck  strikes  against 
this  ridge,  and  not  being  able  to  go  farther  back,  the  ridge  acts 
as  a  fulcrum,  and  starts  the  condyle  over  the  tubercle  of  the 
temporal  bone  into  the  zygomatic  fossa.  The  fact  is  certain, 
that  very  strongly  marked  differences  of  the  glenoid  cavity,  in 
this  particular,  occur  in  different  individuals. 


VOL.  I.— 23 


266  SKELETON. 


CHAPTER   V. 

OF  THE  LIGAMENTS  OF  THE  SPINE. 
Ligaments  of  the  Bodies  of  the  Vertebrce. 

1.  Inter -vertebral  Substance,  (Ligamenta  Interverlebralia, 
Ligamens  Jntervertebraux.) — The  bodies  of  the  true  vertebrae 
are  united  by  a  substance  blending  the  nature  of  ligament  and 
that  of  cartilage,  and,  therefore,  called  fibro  or  ligamento-carti- 
laginous  matter.  It  occupies  all  the  space  between  the  conti- 
guous bodies  of  the  vertebra,  and  adheres  most  closely  to  their 
substance.  This  inter-vertebral  matter  increases  successively 
in  thickness,  as  it  is  placed  lower  down  on  the  spine,  whereby 
the  lumbar  vertebrae  are  mutually  at  a  much  greater  distance 
than  any  others.  The  curvatures  of  the  spine,  as  formerly 
stated,  depend  considerably  upon  the  arrangement  of  this  sub- 
stance: between  the  vertebras  of  the  neck  it  is  thicker  at  its 
.anterior  margin  than  at  the  posterior;  on  the  contrary,  between 
the  dorsal  vertebree  it  is  thinner  in  front.  In  the  loins,  it  is 
again  much  thicker  in  front  than  behind,  and  this  feature  is  un- 
usually marked  between  the  last  lumbar  vertebra  and  the  sa- 
crum. 

This  inter-vertebral  matter  is  formed  of  concentric  lamellae, 
the  texture  of  which  is  ligamentous.  These  lamellae  are  more 
abundant  anteriorly  and  laterally  than  behind.  Their  fibres 
cross  in  every  direction,  leaving  between  them  interstices  or 
cells,  filled  with  a  soft,  pulpy  substance:  this  substance  is  not 
very  obvious  near  the  circumference,  but  in  approaching  the 
centre,  it  becomes  more  and  more  abundant,  as  the  interstices 
are  larger,  until  the  centre  seems  to  be  constituted  almost  -en- 
tirely by  it.  The  pulpy  mass  in  the  centre  is  in  a  state  of  con- 
siderable compression,  which  may  be  proved  by  separating  the 
bodies  of  adjoining  vertebrae,  or  by  making  a  vertical  section 
through  them;  in  which  case  the  pulpy  mass  will  be  freed  from 
compression,  and  will  rise  up  into  the  form  of  a  cone.  This 


LIGAMENTS  OF  THE  SPINE.  267 

experiment  will  succeed  remarkably  well  in  the  loins;  from 
which  it  is  evident,  that  this  mass  is  a  soft  and  elastic  ball,  on 
which  the  bodies  of  the  vertebrae  play. 

The  pulpy  matter  is  proportionately  much  more  abundant  in 
infancy  than  in  the  subsequent  periods  of  life;  it  is  also  much 
softer,  whiter,  and  more  transparent.  In  advanced  life  there  is 
great  diminution  of  its  volume,  as  well  as  of  its  elasticity, 
which  accounts,  in  some  measure,  for  the  comparative  stiffness 
of  the  spine  in  old  people.  The  fibrous  part  in  them  is  always 
more  abundant,  and  is  much  disposed  to  ossify.  When  the 
trunk  is  kept  erect  for  several  hours  in  succession,  it  becomes 
shorter,  from  its  weight  bearing  upon  the  inter-vertebral  mass; 
but  a  short  period  of  rest  in  the  horizontal  position,  restores  if, 
to  its  original  length. 

2.  Anterior  Vertebral  Ligament,  (Fascia  Longitudinalis  An- 
terior, Ligament  Vertebral  Anterior.) — This  ligament  is  placed 
on  the  front  part  of  the  spine,  and  extends  from  the  second 
vertebra  of  the  neck  to  the  first  bone  of  the  sacrum,  inclusively. 
It  increases  gradually  in  breadth,  from  its  commencement  to 
its  termination,  but  is  not  every  where  of  the  same  thickness; 
for  it  is  thin  on  the  neck,  thicker  in  the  thorax,  and  again  be- 
comes thin  in  the  loins:  in  the  latter,  however,  it  is  strengthened 
by  an  accession  of  fibres  from  the  tendinous  crura  of  the  dia- 
phragm. 

This  ligament  adheres  very  closely  to  the  inter-vertebral 
substance,  and  to  the  projecting  margins  of  the  bodies  of  the 
vertebra,  but  less  closely  to  the  middle  or  concave  parts  of  the 
latter.  Its  fibres  do  not  run  out  its  whole  length,  for  the  more 
superficial  extend  from  one  vertebra  or  inter- vertebral  substance, 
to  the  fourth  or  fifth  below:  the  middle  ones  extend  to  the  se- 
cond or  third  below ;  and  the  deepest  seated  are  applied  be- 
tween the  proximat'e  vertebra?  only.  In  general,  more  of  the 
fibres  are  inserted  into,  and  arise  from  the  fibro-cartilaginous 
matter  than  the  bones.  In  several  parts,  but  particularly  in  the 
neck,  small  slips  are  sent  off  obliquely  to  the  vertebra  below. 
The  laminae  of  this  ligament  leave  intervals  between  them  for 
the  passage  of  blood  vessels. 

Beneath  the  anterior  vertebral  ligament  are  found  a  great 
many  short  and  insulated  ligamentous  fibres,  extended  oblique- 


268  SKELETON. 

Iy  from  one  vertebra,  to  another  which  is  contiguous.  These 
fibres  have  different  directions,  and  cross  each  other  at  acute 
angles;  they  adhere  very  closely  to  the  fibro-cartilaginous  mat- 
ter, and  leave  interstices  between  themselves,  through  which 
the  anterior  vertebral  ligament  adheres  to  the  same  substance. 
Moreover,  there  are  at  the  sides  of  the  bodies  of  the  vertebrae, 
a  number  of  short  straight  fibres,  passing  from  the  edge  of  the 
bone  above  to  the  edge  of  the  bone  below. 

3.  Posterior  Vertebral  Ligament,  (Ligamentum  Commune 
Posterius,  Ligament  Vertebral  Posterieur.) — This  is  placed  on 
the  hind  part  of  the  bodies  of  the  vertebra,  within  the  spinal 
canal,  and  extends  from  the  cuneiform  process  of  the  occiput 
just  beyond  the  foramen  magnum,  to  the  os  coccygis.  It  is 
more  narrow  and  thick  in  the  thoracic  vertebrae  than  else- 
where. At  each  inter-vertebral  substance  it  increases  in 
breadth  and  adheres  more  closely,  whereas,  opposite  the  body 
of  a  vertebra  it  is  narrower  and  more  loose,  by  which  arrange- 
ment a  kind  of  serrated  or  unequal  edge  is  formed  on  each 
side. 

This  ligament  is  more  dense  and  compact  than  the  anterior, 
and  presents  a  smooth,  shining  surface,  resembling  a  tendinous 
expansion.  Its  fibres,  also,  do  not  run  individually  the  whole 
length  of  the  spine,  but  are  in  laminae;  the  more  superficial  of 
which  have  their  fibres  inserted  into  the  fourth  or  fifth  inter- 
vertebral  substance  or  vertebra,  below  their  origin.  The  mid- 
dle laminae  are  inserted  into  the  second  or  third  below,  and  the 
deeply  seated  into  the  first  below.  The  blood  vessels  do  not 
penetrate  the  ligament,  but  pass  by  its  sides  into  the  vertebrae. 
The  superior  extremity  of  this  ligament  going  from  the  second 
vertebra  to  the  margin  of  the  foramen  magnum,  is  sometimes 
considered  as  distinct. 


Ligaments  of  the  Processes  of  the  Vertebrce. 

1.  Articulation  of  the  Oblique  Processes. — These  processes 
are  faced  with  cartilage,  and  a  synovial  capsule  is  displayed 
upon  them  so  as  to  shut  up  completely  the  cavity  of  the  articu- 
lation. The  capsular  ligament  is  not  uniform  and  fully  deve- 


LIGAMENTS  OF  THE  SPINE.  269 

loped,  but  is  represented  by  a  few  irregular  fibres,  passing  from 
one  bone  to  the  other. 

2.  Articulation  of  the  Spinous  Processes. — With  the  exception 
of  the  neck,  ligamentous  fibres  are  found  to  occupy  the  spaces 
between  all  the  spinous  processes,  by  passing  from  the  spinous 
process  above,  to  the  spinous  process  below.     Muscles  supply 
their  places  in  the  neck,  and  in  the  upper  part  of  the  thorax. 
These  ligaments  have  much  of  a  cellular  structure  above,  but 
in  their  descent  they  become  more  ligamentous  and  large,  till, 
in  the  loins,  they  assume  a  very  decided  character,  and  have  a 
quadrilateral  shape. 

At  the  extremities  of  the  spinous  processes  there  is,  also,  a 
ligamentous  band,  belonging  to  the  dorsal  and  lumbar  verte- 
brae; commencing  at  the  seventh  cervical,  it  terminates  on  the 
spinous  processes  of  the  sacrum.  It  is  thin  in  the  back,  but  on 
the  loins  it  is  very  thick,  and  so  blended  with  the  tendinous 
origins  of  the  muscles,  that  it  is  not  very  distinguishable  from 
them.  The  fibres  of  which  it  consists  are  of  unequal  lengths, 
being  extended  between  two,  three,  four,  or  five  vertebrae,  ac- 
cordingly as  the  fibres  are  superficial  or  deep-seated. 

3.  Owing  to  the  shortness  of  the  spinous  processes  of  the 
neck,  an  arrangement  exists  there  called  Ligamentum  Nuchas, 
(Ligament  Cervical,)  or  the  Descending  Ligament  of  Diemer- 
broeck.     This  ligament,  though  continuous  with  the  one  last 
described,  may  be  considered,  for  the  sake  of  perspicuity,  as 
distinct.     It  begins,  therefore,  at  the  seventh  cervical  spine,  as- 
cends between  the  muscles  of  the  opposite  sides  of  the  neck,  and 
is  inserted  into  the  posterior  occipital  protuberance.    It  is  blend- 
ed very  much  with  the  tendons  of  muscles,  and  is  distinguished 
from  them  with  some  difficulty,  occasionally..  Its  posterior  mar- 
gin is  thick,  but  the  anterior  is  a  thin  membranous  expansion, 
which  runs  to  the  ends  of  the  spinous  processes  of  the  cervical 
vertebra3,  and  to  the  vertical  ridge  of  the  occipital  bone,  lead- 
ing from  the  occipital  protuberance  to  the  foramen  magnum. 
The  ligamentum  nuchre,  therefore,  forms  a  complete  septum  be- 
t.  veen  the  muscles  of  the  opposite  sides  of  the  neck,  and  is  con- 
tinuous with  the  sheaths  in  which  they  play.     In  quadrupeds  it 
is  remarkably  strong ;  but  in  man,  who,  from  the  proportions 

23* 


270  SKELETON. 

of  his  head  and  his  erect  position,  keeps  the  head  nearly  in 
equilibrium,  it  is  comparatively  feeble. 

4.  Articulation  of  the  Bony  Bridges  of  the  Vertebra. — The  in- 
tervals between  the  vertebrae,  at  the  posterior  part  of  the  spinal 
canal,  are  filled  up  by  the  Yellow  Ligaments,  (Ligamenta  Flavce,) 
so  called  from  their  peculiar  colour.  These  intervals  exist  be- 
tween all  the  true  vertebras,  being  bounded  laterally  by  their 
oblique  processes,,  and  are  very  considerable  in  the  loins,  par- 
ticularly that  below  the  last  vertebra;  they  are  not  so  large  in 
the  neck,  and  are  still  smaller  in  the  back ;  and  their  shape  va- 
ries considerably  in  the  several  portions  of  the  spine. 

The  yellow  ligaments  are  two  in  number,  forming  a  pair  in 
each  of  these  intervals :  the  two  approach,  behind,  at  an  angle, 
in  a  line  with  the  spinous  processes,  but  are  kept  separated  by 
a  small  vertical  fissure  filled  up  with  cellular  substance.  They 
extend  to  the  oblique  processes  laterally;  are  connected  to  the 
anterior  face  of  the  bony  bridge  of  the  vertebra  above;  where- 
as, they  are  inserted  into  the  superior  margin  of  that  of  the  ver- 
tebra below.  From  this  arrangement,  the  yellow  ligaments 
may  be  best  seen  on  the  side  of  the  spinal  canal.  The  angle 
which  they  form,  behind,  is  continuous  with  the  ligaments  be- 
tween the  spinous  processes. 

These  yellow  ligaments  are  smooth  and  shining  on  their  an- 
terior surfaces,  but  behind  they  are  rough  and  unequal.  Their 
fibres  are  numerous  and  extremely  compact,  their  strength  is, 
therefore,  very  great.  Their  elasticity  is  well  marked  and  pe- 
culiar to  them,  and  assists  greatly  in  erecting  the  spine  when  it 
has  been  curved  forwards.  Bichat  says  that  there  is  but  little 
cellular  tissue  between  their  fibres:  that  they  are  dissolved  with 
extreme  difficulty  in  boiling  water,  and  resist  its  action  to  such 
a  degree,  that  it  is  manifest  they  contain  much  less  gelatine  than 
the  greater  number  of  analogous  organs. 

The  first  pair  of  yellow  ligaments  is  between  the  second  and 
third  cervical  vertebras,  and  the  last  between  the  last  lumbar 
and  the  sacrum ;  there  are,  consequently,  only  twenty-three  pairs 
in  all. 

Particular  Articulations  of  the  Spine. 

1.  Articulation  of  Occiput  with  Atlas. — The  Anterior  Ligament 
s  placed  at  the  anterior  part  of  the  occipital  foramen,  and  ex- 


LIGAMENTS  OF  THE  SPINE.  271 

tends  from  it  to  the  corresponding  edge  of  the  atlas.  On  its 
centre  in  front  is  a  fasciculus,  which  being  narrow  and  some- 
what rounded,  descends  from  the  middle  of  the  cuneiform  pro- 
cess to  terminate  in  the  tubercle  on  the  front  of  the  atlas ;  and 
consists  in  parallel  fibres.  The  remainder  is  called  by  Caldani, 
Membrana  annuli  anterioris  atlantis,  (Ligament  occiptto-atloidien 
anterieur.)  It  occupies  and  shuts  up  the  whole  space  between 
the  basilar  process  of  the  os  occipitis,  from  which  it  takes  its 
origin  near  the  occipital  foramen ;  and  the  anterior  arch  of  the 
atlas,  in  the  superior  margin  of  which  it  is  lost:  in  it  are  many 
oblique  fibres,  which  run  from  within  outwards. 

The  posterior  Ligament  is  placed  at  the  back  part  of  the  oc- 
cipital foramen,  and  extends  from  it  to  the  corresponding  edge 
of  the  atlas.  It  is  called  by  Caldani,  Membrana  annuli  poste- 
rioris  atlantis,  (Ligament  occipito-atloidien  posterieur;)  and  arising 
from  the  whole  posterior  margin  of  the  occipital  foramen  be- 
tween the  condyles,  it  is  extended  to  the  upper  contiguous  mar- 
gin of  the  atlas,  so  as  to  fill  up  completely  this  space.  Bichat 
says  that  it  also  consists  in  two  laminae,  the  anterior  of  which 
is  fibrous,  and  runs  into  the  dura  mater  of  the  spine  instead  of 
into  the  bone:  the  posterior  is  of  a  much  looser  texture,  and  re- 
sembles common  cellular  substance.  A  part  of  this  membrane 
runs  obliquely  from  the  transverse  process  of  the  atlas  to  the 
part  of  the  occiput  just  beneath  the  insertion  of  the  rectus  pos- 
ticus  minor. 

The  articulating  surfaces  of  the  condyles,  and  the  superior 
oblique  processes  of  the  first  vertebra,  are  covered  with  carti- 
lage, and  furnished  with  a  synovial  membrane  arising  from 
their  margins.  On  the  exterior  of  the  synovial  membrane  there 
are  irregular  ligamentous  fibres  going  between  the  bones,  and 
forming  a  capsule. 

2.  Articulation  of  the  second  Vertebra  with  the  Occiput,  and 
with  the  first. — The  second  vertebra  has  no  articular  surface 
joining  the  occiput,  but  some  strong  ligaments  are  passed  be- 
tween them.  When  the  posterior  vertebral  ligament  is  removed 
at  its  commencement  from  the  occipital  bone,  we  see  on  each 
side  of  it,  and  beneath  it,  ligamentous  bands  (Lacerti  Liga- 
mentosi,)  coming  from  the  internal  face  of  the  os  occipitis,  to 


272  SKELETON. 

be  affixed  to  the  body  of  the  second  vertebra  behind.  Some 
of  these  fibres  arise  from  the  margin  of  the  occipital  foramen, 
and  others  from  the  internal  face  of  the  condyloid  processes.* 
They  are  joined  at  their  external  margins  by  a  few  fibres  from 
the  first  vertebra,  near  its  upper  oblique  process. 

The  Transverse  Ligament  (Ligamentum  Transversale  At- 
lantis, Ligament  Transverse,)  is  placed  immediately  behind  the 
processus  dentatus,  and  divides  the  atlas  into  two  unequal  rings 
by  being  stretched  from  one  side  to  the  other.  It  is  larger  in 
the  middle  than  at  the  extremities,  and  has  the  latter  inserted 
into  the  little  tubercle  at  the  internal  side  of  the  atlas,  between 
the  upper  and  the  lower  articular  surfaces.  It  is^a  thick,  strong 
fasciculus  of  fibres,  and  binds  the  processus  dentatus  so  as  to  form 
for  it  a  sprt  of  collar,  amounting  to  about  one-fourth  of  a  circle. 
The  superior  appendix  of  this  ligament  arises  by  a  broad  base 
from  the  anterior  margin  of  the  foramen  magnum,  and  termi- 
nates below  by  a  narrow  .end  in  the  upper  margin  of  the  trans- 
verse ligament.  The  inferior  appendix  arises  from  the  lower 
edge  of  the  transverse  ligament,  and  is  attached,  by  a  some- 
what converging  end,  into  the  posterior  face  of  the  body  of  the 
vertebra  dentata. 

The  surfaces  of  contact  belonging  to  the  processus  dentatus, 
and  to  the  anterior  ring  of  the  atlas,  are  covered  with  cartilage, 
and  have  a  synovial  membrane,  so  as  to  form  a  perfect  joint 
called  the  vaginal  ligament.  A  joint  with  a  distinct  synovial 
membrane  is,  in  like  manner,  formed  between  the  posterior  face 
of  the  processus  dentatus  and  the  anterior  of  the  transverse  li- 
gament, where  they  come  into  contact. 

The  Oblique  or  Moderator  Ligaments  (Lig.  Later  alia,  Liga- 
mens  Odontoidiens)  are  two,  one  on  either  side  of  the  tooth-like 
process.  They  may  be  seen  most  advantageously  by  cutting 
through  the  transverse  ligament,  and  arise  from  the  side  and 
summit  of  the  processus  dentatus,  to  be  inserted  into  the  inter- 
nal margin  of  the  occipital  condyle.  They  are  thick,  short,  and 
strong,  and  consist  in  parallel  fibres ;  their  lower  margin  has  been 
considered  as  a  distinct  ligament  by  Weitbrecht,  and  described 

*  Caldani,  Icon.  Anat.  Explicatio,  vol.  i.  p.  255. 


LIGAMENTS  OF  THE  SPINE.  273 

by  him  as  coming  from  the  neck  of  the  process.     There  is  some 
cellular  tissue  at  the  front,  in  which  the  process  revolves. 

The  Middle  Straight  Ligament,  (Lig.  Medium  Rectum,  Liga- 
ment droit  Moyen,)  or  Occipito-Dentate,  arises  from  all  that 
part  of  the  summit  of  the  processus  dentatus  anteriorly  which 
is  between  the  moderator  ligaments,  and  is  inserted  into  all  that 
part  of  the  interior  circumference  of  the  foramen  magnum  be- 
tween the  insertion  of  the  moderator  ligaments.  It  is  a  thin 
ligamentous  membrane,  disposed  to  form  in  its  middle  a  verti- 
cal fissure,  separating  its  two  halves.  It  cannot  be  seen  well, 
unless  the  whole  membrana  annuli  anterioris  be  dissected  away, 
and  the  anterior  bridge  of  the  first  vertebra  sawed  off;  it  will 
then  be  found  immediately  behind  the  bursa  of  the  processus 
dentatus.  It  is  separated  from  the  superior  appendix  of  the 
transverse  ligament  by  a  layer  of  condensed  fatty  substance. 
This  ligament  should  not  be  confounded  with  the  superior  ap- 
pendix of  the  transverse  ligament,  nor  with  the  beginning  of  the 
posterior  vertebral  ligament,  as  has  been  done  by  Bichat  and 
others.  The  difference  is  well  established  by  Caldani,  as  it  lies 
deeper  than  either  of  them  when  viewed  from  the  vertebral 
cavity;  though,  from  the  close  connexion  of  the  fibres  of  the 
ligaments  among  themselves,  as  well  as  with  others,  the  mistake 
may  readily  occur.* 

The  Articulation  between  the  oblique  process  of  the  first  and 
of  the  second  cervical  vertebra  is  very  moveable,  as  the  atlas 
is  permitted  to  revolve  around  the  processus  dentatus  to  the 
amount  of  one-fourth  of  a  circle  at  least.  This  articulation  has 
a  synovial  capsule  which  is  strengthened  by  an  anterior  and  by 
a  posterior  ligament. 

The  anterior  ligament  of  the  articulation  between  the  oblique 
processes  arises  from  the  inferior  margin  of  the  atlas  and  from 
its  anterior  tubercle,  and  is  inserted  into  the  base  of  the  pro- 
cessus dentatus,  and  into  the  front  of  the  body  of  the  second 
vertebra.  The  fibres  of  the  latter  insertion  are  long  and  fre- 
quently distinct  from  the  first. 

*  Its  existence  is,  however,  scarcely  to  be  considered  uniform,  as  it  is  often 
wanting  where  the  processus  dentatus  is  very  long,  for  example  when  it  reaches 
the  anterior  part  of  the  foramen  magnum  and  forms  a  joint  there,  as  it  sometimes 
does. 


274  SKELETON. 

The  posterior  ligament  is  placed  between  the  first  and  second 
vertebrae  behind,  and  is  connected  to  their  contiguous  margins 
so  as  to  fill  up  the  interval  between  them,  and  to  supply  the 
place  of  the  yellow  ligaments.  It  is  extremely  loose  and  thin, 
so  as  not  to  interfere  in  the  movements  of  the  vertebrae,  and  is 
almost  of  a  cellular  structure. 

The  syuovial  membrane  of  these  oblique  processes  is  unu- 
sually lax,  and  is  reflected  from  the  margin  of  the  one  articular 
surface  to  the  other.  It  is  in  contact  in  front  with  the  anterior 
ligament;  behind  with  the  posterior  and  with  much  cellular 
substance;  internally  with  the  ligaments  within  the  spinal  canal, 
and  externally  with  the  carotid  artery.  The  latter  obtains  from 
it  a  serous  covering,  without  which,  according  to  Bichat,  it 
would  be  bathed  in  the  synovial  fluid. 


CHAPTER  VI. 

OF  THE  LIGAMENTS  OF  THE  PELVIS. 

THE  mode  of  junction  between  the  sacrum  and  the  last  lum- 
bar vertebra,  is,  in  every  respect,  the  same  as  that  described 
for  the  bones  of  the  spine  generally,  with  the  addition  of  a  liga- 
ment on  each  side,  sometimes  met  with,  called  Sacro-vertebral, 
which  arises  from  the  transverse  process  of  the  last  lumbar 
vertebra,  and  going  obliquely  downwards,  is  inserted  into  the 
superior  part  of  the  sacrum  by  blending  itself  with  the  anterior 
fibres  of  the  sacro-iliac  junction. 

The  Sacrum  is  united  to  the  coccyx  by  a  fibro-cartilaginous 
substance,  resembling  that  between  the  bodies  of  the  true  ver- 
tebrae, with  the  exception  of  there  being  less  pulpy  matter  in 
its  centre,  and  of  its  fibrous  lamellae  being  more  uniform.  The 
bones  of  the  coccyx  are  also  united  with  one  another  in  the 
same  way ;  in  consequence  of  which  they  are  very  flexible  till 
the  approach  of  old  age. 

The  Anterior  Coccygeal  Ligament,  (Lig.  Sacro-coccygeum 


LIGAMENTS  OF  THE  PELVIS.  275 

dnterius)  is  placed  on  the  forepart  of  the  latter  bone ;  runs  its 
whole  length,  and  arises  from  the  inferior  extremity  of  the  sa- 
crum. Its  fibres  are  rather  indistinct,  from  their  being  blended 
with  fat :  on  the  lateral  margins  of  the  coccyx  they  are  rather 
better  marked. 

The  Posterior  Coceygeal  Ligament,  (Lig.  Sacro-coccygeum 
Posterius,)  as  its  name  implies,  is  placed  on  the  back  part  of  the 
coccyx.  It  arises  from  the  inferior  margin  of  the  spinal  canal 
of  the  sacrum,  arid  forms  a  sort  of  membranous  expansion, 
which  passes  the  first  bone  of  the  coccyx,  and  is  inserted  into 
the  second.  There  are  also  a  few  other  ligamentous  fibres  con- 
necting the  bones  of  the  coccyx. 

The  Ilio  Lumbar  ligament  (Lig.  llio  Lumbare)  arises  from 
the  transverse  process  of  the  last  lumbar  vertebra,  and  from  its 
inferior  oblique  process,  and  going  outwards  is  inserted  for  two 
inches  into  the  crista  of  the  ilium.  It  is  often  blended  with 
adipose  matter,  which  separates  it  into  several  fasciculi.  Cal- 
dani  describes  it  as  two  ligaments,  making  a  distinction  between 
the  one  part  from  the  transverse,  and  the  other  from  the  ob- 
lique process. 

The  Sacro-Iliac  Articulation  is  formed  by  the  corresponding 
surfaces  of  the  sacrum  and  ilium.  Each  bone  is  incrusted  with 
its  own  cartilage,  the  one  on  the  sacrum  being  somewhat  more 
thick.  Their  surfaces  are  slightly  rough,  and  between  them 
exists  a  thick  yellow  fluid  in  a  very  small  quantity,  which  lu- 
bricates them,  and  is  more  abundant  in  early  life. 

The  Sacro- Spinous  Ligament  (Lig.  Sacro  Spinosum)  is 
placed  superficially  on  this  articulation  behind.  It  is  very 
strong,  flat,  long,  and  perpendicular.  It  consists  of  two  lamince, 
of  which  the  more  superficial  arises  from  the  posterior  supe- 
rior spinous  process  of  the  ilium,  and  is  inserted  into  the  fourth 
transverse  process  of  the  sacrum.  The  deep-seated  lamina 
arises  from  the  same  point,  and  is  inserted  into  the  third  trans- 
verse process  of  the  sacrum.  Bichat  describes,  connected  with 
the  inferior  margin  of  this  ligament,  a  fasciculus,  which  comes 
from  the  posterior  inferior  spinous  process  of  the  ilium. 


276  SKELETON. 

The  Sacro-Iliac  Ligament  (Lig.  Sacro-lliacum)  is  next  to  the 
articular  faces  of  the  bones.  It  surrounds  the  joint,  but  is  much 
stronger  on  its  posterior  face.  It  consists  in  an  assemblage  of 
ligamentous  fasciculi,  some  of  which  have  obtained,  by  the 
writers  on  Syndesmology,  particular  names,  but  which  it  would 
scarcely  add  to  the  student's  information  to  designate.  On  the 
front  of  the  joint  this  ligament  is  uniform,  and  consists  of  a 
plane  of  short,  strong  fibres,  passing  from  the  margin  of  one 
bone  to  that  of  the  other.  But,  on  the  posterior  surface,  it  is 
much  more  irregular,  and  arises  from  the  first  two  eminences 
near  the  lateral  margin  of  the  sacrum,  and  from  that  surface  of 
the  sacrum  between  these  eminences  and  its  articular  face. 
From  thence  the  sacro-iliac  ligament  goes  to  be  inserted  into 
the  rough  surface  of  the  ilium,  immediately  behind  its  articular 
face;  it  fills  up  there  a  considerable  space,  and,  from  its  posi- 
tion, must  be  extremely  irregular.  Its  strength  is  so  great, 
that  in  forcing  the  joint  the  ligament  does  not  rupture,  but  parts 
preferably  from  the  surface  of  the  ilium,  and  sometimes  brings 
with  it  a  lamella  of  bone. 

The  bones  of  the  pelvis  are  also  fastened  by  two  other  very 
strong  ligaments,  the  sacro-sciatic. 

The  Posterior  Sacro-Sciatic  (Lig.  Sacro-lschiadicum  majus) 
is  the  most  considerable  of  the  two.  It  arises  from  the  poste- 
rior inferior  spinous  process  of  the  ilium,  from  the  margin  of 
the  sacrum  below  this  bone,  and  somewhat  from  its  posterior 
surface,  and  from  the  first  bone  of  the  coccyx.  It  goes  down- 
wards and  outwards,  becomes  thicker  in  its  middle,  but  nar- 
row; it  then  spreads  out,  and  is  inserted  along  the  internal  mar- 
gin of  the  tuberosity  of  the  ischium.  Its  anterior  extremity  is 
extended  along  the  internal  face  of  the  crus  of  the  ischium  for 
some  distance,  and  has  the  obturator  internus  muscle  adhering 
to  it.  Its  fibres,  where  they  converge  from  their  origin,  are 
separated  into  planes  by  masses  of  fat  and  by  blood  vessels. 

The  Anterior  Sacro-Sciatic  Ligament  (Lig.  Sacro-lschiadi- 
cum minus]  is  much  smaller  than  the  other,  and  is  placed  in 
front  of  it.  It  arises  from  the  margin,  and  somewhat  from  the 
posterior  surface  of  the  sacrum,  below  the  ilium ;  and  from  the 
lateral  margin  of  all  the  bones  of  the  coccyx.  The  fibres  con- 


LIGAMENTS  OF  THE  PELVIS.  277 

verge,  and  are  inserted  into  the  spinous  process  of  the  ischium, 
by  embracing  it.  The  fibres  constituting  its  base-,  have  their 
fasciculi  separated  by  cellular  adipose  matter  and  by  vessels, 
and  are  also  intermingled  with  the  fibres  of  the  coccygeus  mus- 
cle, and  of  the  posterior  sacro-sciatic  ligament. 

The  two  sacro-sciatic  ligaments  supply,  in  some  degree,  the 
place  of  bone,  and  form  a  part  of  the  inferior  lateral  parietes  of 
the  pelvis.  They  convert  the  sciatic  notch  into  a  foramen,  or, 
rather,  form  with  it  two  foramina;  the  upper  and  larger  of 
which  transmits  the  pyriformis  muscle,  the  sciatic  nerve,  and 
the  gluteal  blood  vessels;  while  the  lower,  placed  between 
the  insertion  of  the  two  ligaments,  transmits  the  obturator  in- 
ternus  muscle,  and  brings  the  internal  pudic  artery  into  the 
pelvis. 

The  Obturator  Ligament  (Membrana  Obturatoria)  is  extend- 
ed across  the  foramen  thyroideum,  so  as  to  close  it  up,  with 
the  exception  of  a  foramen  at  its  upper  part,  for  transmitting 
the  obturator  vessels  and  nerves.  It  is  a  thin,  but  strong  mem- 
brane, having  its  fasciculi  of  fibres  passing  in  various -directions, 
and  arising  from  the  margin  of  the  foramen.  It  affords  origin 
to  many  of  the  fibres  of  the  obturator  muscles.  Sometimes 
portions  of  it  are  defective. 

The  Articulation  of  the  Pubes  is  formed  between  the  bodies 
of  the  two  ossa  pubis.  It  consists  principally  in  a  fibro-carti- 
laginous  matter,  which  has  a  strong  resemblance  to  that  of  the 
vertebras.  When  the  bones  are  torn  apart  by  bending  them 
forwards,  the  fibrous  arrangement  becomes  very  apparent,  and 
is  seen  to  consist  in  concentric  lamella?,  the  fibres  of  which  cross 
one  another.  Sometimes  in  the  male,  but  most  frequently  in 
the  female,  the  posterior  third  of  the  articulation  is  deprived  of 
these  fibres,  in  place  of  which  we  find,  in  the  middle  of  the 
cartilage,  a  small  longitudinal  cavity,  the  surface  of  which  is 
smeared  with  a  kind  of  mucosity.  There  is  no  central  pulpy 
matter  in  this  articulation,  as  there  is  between  the  vertebras.  On 
its  posterior  surface  it  often  makes  a  ridge  projecting  into  the 
cavity  of  the  pelvis.  From  frequent  observations  made  in  our 
dissecting-rooms,  I  have  no  doubt  that  this  articulation  is  al- 
ways very  much  relaxed  in  the  parturient  and  pregnant  female, 

VOL.  I.— 24 


278  SKELETON. 

which  is  manifested  not  by  the  bones  separating,  but  by  their 
sliding  upwards  and  downwards  with  great  readiness.  The  sa- 
cro-iliac  junction  also  becomes  relaxed.  It  was  upon  the  ob- 
servation of  these  facts,  that  the  clebrated,  but  now  exploded, 
Sigaultian  operation  was  founded. 

The  Anterior  Pubic  ligament  is  not  very  distinct.  It  lies  in 
front  of  the  last  articulation,  and  consists  in  a  few  oblique  and 
transverse  fibres  gomg  from  the  one  bone  to  the  other. 

The  Sub  or  Inter-Pubic  Ligament  (Lig.  Pubis  Inferius)  oc- 
cupies the  summit  of  the  arch  of  the  pelvis.  It  is  of  a  trian- 
gular form,  about  half  an  inch  in  breadth,  and  passes  from  the 
margin  of  the  crus  of  the  pubes  of  the  one  side,  to  a  corre- 
sponding line  on  the  other.  It  is  remarkably  strong,  and  is  ra- 
ther more  so  below  than  above.  It  seems  rather  an  extension 
of  the  ligament  of  the  symphysis  pubis,  than  a  distinct  struc- 
ture. 


CHAPTER    VII. 

ARTICULATIONS    OF  THE   THORAX. 

Posterior  Articulations  of  the  Ribs. 

As  mentioned,  in  the  account  of  the  bones,  the  articulations 
here  are  double;  being  formed  at  one  point  between  the  heads 
of  the  ribs  and  the  bodies  of  the  vertebrae  with  the  inter-verte- 
bral matter;  and  at  the  other,  between  the  tubercles  of  the  ribs 
and  the  transverse  processes.  In  either  case  the  respective 
surfaces  are  covered  by  articular  cartilage,  and  have  a  syrio- 
vial  membrane.  The  first  joint  is  the  Costo- vertebral,  and  the 
second  the  Costo-transverse. 

1.  The  Costo- vertebral  articulation  presents  an  anterior  liga- 
ment, an  inter-articular  ligament,  and  two  synovial  membranes. 
The  Anterior  or  Radiating  Ligament,  (Lig.  Capituli  Costa- 


ARTICULATIONS  OF  THE  THORAX.  279 

rum,)  is  fixed,  as  its  name  expresses,  in  front  of  the  joint.  It 
arises  from  the  margin  of  the  head  of  the  rib  by  the  whole 
breadth  of  the  latter,  and  diverging  towards  the  spine,  is  fixed, 
by  its  superior  fibres,  into  the  vertebra  above;  by  its  inferior 
fibres,  into  the  vertebra  below;  and,  by  its  middle  fibres,  into 
the  inter-vertebral  substance.  It  is  a  thin,  flat,  fibrous  mem- 
brane, leaving  intervals  in  it  for  the  passage  of  blood  vessels, 
and  may,  indeed,  be  considered  as  a  capsule  to  the  articula- 
tion, and  is  frequently  described  as  such.  The  inter-articular 
ligament  passes  from  the  ridge  on  the  head  of  the  rib,  to  a  cor- 
responding line  of  the  inter-vertebral  substance.  It  is  short 
and  strong,  and  divides  the  articulation  of  the  head  of  the  rib 
into  two  cavities,  which  have  no  communication.  It  is  in 
consequence  of  the  latter,  that  there  are  two  synovial  mem- 
branes to  the  head  of  every  rib  which  has  a  double  articular 
face;  but  the  ribs  which  are  articulated  with  a  single  vertebra, 
as  the  first,  the  eleventh,  and  the  twelfth,  have  not  the  inter- 
articular  ligament,  and,  therefore,  only  one  synovial  mem- 
brane. 

The  synovial  membranes  are  not  very  apparent,  neither  is 
the  fluid  abundant;  the  cavity  is  occasionally  very  small  from 
the  encroachment  of  the  inter-articular  ligament.  Anchylosis 
occasionally  takes  place  here,  but  it  is  much  less  frequent  than 
in  the  anterior  articulations  of  the  thorax. 

2.  The  Costo-transverse  articulation  has,  in  addition  to  the 
joint  formed  between  the  tubercle  of  the  rib  and  the  end  of  the 
transverse  process,  several  ligamentous  fasciculi  which  pass  in 
varied  directions. 

Its  synovial  membrane  is  much  more  distinct  than  in  the  pre- 
ceding articulation,  and  contains  more  synovia.  The  joint  is 
more  loose,  and  is  never  anchylosed,  except  by  disease.  There 
are  a  few  fibres  around  it  having  the  semblance  of  a  capsule. 

The  Internal  Transverse  Ligament  (Ligamentum  Transver- 
sarium  Internum,  or  Costo-Transversarium  Inferius,)  arises  from 
the  inferior  margin  of  the  transverse  process,  between  its  root 
and  external  extremity,  and  proceeding  downwards  and  in- 
wards, is  inserted  into  the  upper  margin  of  the  neck  of  the  rib 
below.  In  many  of  the  ribs  there  is  a  plane  of  ligamentous 
fibres  parallel  with  this  ligament,  but  just  behind,  and  arising 


280  SKELETON. 

from  a  more  posterior  situation  of  the  transverse  process  to  go 
to  the  neck  of  the  rib,  somewhat  more  towards  the  tubercle  of 
the  latter.  It  is  designated  by  some  writers  as  the  posterior 
transverse  ligament,  but  the  distinction  between  it  and  the  lig. 
trans,  internum  is  so  slight  that  it  scarcely  seems  necessary  to 
consider  them  apart.  The  Internal  Transverse  Ligament  is 
much  more  conspicuous  in  the  middle  eight  ribs,  and  in  ex- 
tremely emaciated  subjects;  in  others,  it  is  obscured  by  cellu- 
lar adipose  matter  around  the  heads  of  the  ribs. 

The  External  Transverse  Ligament  (Ligamentum  Transver- 
sarium  Externum,  or  Costo-Tmnsversarium  Posterius)  is  a  well- 
marked  quadrangular  plane  of  ligamentous  fibres,  placed  on  the 
posterior  surface  of  the  costo-transverse  articulation.  It  arises 
from  the  extremity  of  the  transverse  process,  and  going  out- 
wardly, is  inserted  into  the  proximate  rib,  just  beyond  its  arti- 
cular tubercle. 

The  Middle  Costo-Transverse  Ligament  (Ligamentum  Cer- 
vicum  Costarum,  or  Costo-Transversarium  Medium)  is  extended 
between  and  concealed  by  the  neck  of  the  rib  and  the  contigu- 
ous transverse  process,  and  cannot  be  seen  well  without  sepa- 
rating them,  or  by  sawing  through  their  length.  It  is  a  collec- 
tion of  fibres,  somewhat  irregular,  resembling  condensed  cellu- 
lar substance,  and  slightly  red. 

These  posterior  articulations  all  require  a  patient  dissection, 
as  they  are  surrounded  by  small  masses  of  adipose  matter, 
have  the  intercostal  nerves  and  blood  vessels  in  contact  with 
them  before,  and  the  muscles  of  the  spine  behind.  The  liga- 
ments between  the  transverse  processes  and  the  ribs  are,  of 
course,  not  found  in  the  eleventh  and  twelfth,  from  the  bones 
not  touching  there. 

Besides  what  has  been  described,  an  aponeurosis  or  liga- 
mentous membrane  is  extended  from  the  transverse  process  of 
the  first  and  second  lumbar  vertebrae,  to  the  inferior  margin  of 
the  last  rib.  A  ligamentous  membrane  is  also  found  near  the 
spine,  extended  between  the  contiguous  margins  of  the  last 
two  ribs. 


ARTICULATIONS  OF  THE  THORAX.  281 


Anterior  Articulations  of  the  Ribs. 

The  surface  of  each  pit  in  the  side  of  the  sternum  is  covered 
by  a  thin  cartilaginous  plate,  to  receive  the  corresponding  car- 
tilage of  the  rib,  and  the  articulation  presents  an  anterior  and 
a  posterior  ligament,  also  a  synovial  capsule. 

The  anterior  ligament  arises  from  the  extremity  of  the  car- 
tilage, and,  going  over  the  front  of  the  sternum,  radiates  very 
considerably  in  every  direction.  Some  of  its  fibres  are  con- 
tinuous with  the  corresponding  fibres  of  the  opposite  side; 
others  are  lost  in  the  periosteum  and  in  the  tendinous  origin  of 
the  great  pectoral  muscle;  others  join  the  fibres  of  the  ligament 
above,  and  of  that  below.  The  more  superficial  the  fibres  are, 
the  longer  they  become;  but  the  more  deeply  seated  pass  only 
from  the  margin  of  the  cartilage  to  the  margin  of  the  cavity  in 
the  sternum.  The  thick  ligamentous  covering  found  on  the 
front  of  the  sternum,  may  be  considered  as  only  the  continua- 
tion of  these  anterior  ligaments.  The  fibres  from  the  two  lower 
articulations  on  the  opposite  side,  form,  by  their  junction,  a 
striking  triangular  ligamentous  plane,  just  on  the  lower  end  of 
the  second  bone  of  the  sternum.  Besides  which,  there  are  se- 
veral strong  ligamentous  fasciculi  running  in  a  great  variety  of 
directions. 

The  posterior  ligament  has  a  similar  arrangement  with  the 
anterior,  in  the  radiation  of  its  fibres  into  the  contiguous,  liga- 
ments, and  in  their  origin  from  the  costal  cartilage.  Altogether 
they  form,  on  the  posterior  face  of  the  sternum,  a  strong,  smooth 
covering,  the  fibres  of  which  do  not  run  in  fasciculi,  but  present 
a  uniform  polished  membrane,  and  are  closely  interwoven  with 
each  other.  Some  of  these  fibres  are  longitudinal,  and,  of 
course,  cannot  be  referred  to  the  posterior  ligaments,  but  are 
independent  of  them. 

The  synovial  membrane,  though  its  existence  is  admitted,  is 
not  in  a  very  distinct  state.  It  scarcely  gives  a  polish  to  the 
articular  surfaces,  and  has  so  little  looseness  in  its  reflection 
from  the  one  to  the  other,  as  to  indicate  clearly  that  but  an  in- 

24* 


282  SKELETON. 

considerable  motion  is  admitted  in  these  joints.  The  synovia 
is  in  very  small  quantity,  not  abundant  enough  for  satisfactory 
examination,  and  its  character  is  rather  inferred  than  proved. 
The  first  cartilage  is  continuous  with  the  sternum,  and  not  se- 
parated from  it  by  any  joint,  except  in  rare  instances.  The 
second  cartilage  has  its  joint  with  the  sternum,  separated  into 
two,  one  above  and  the  other  below,  by  a  ligamentous  parti- 
tion resembling  that  at  the  heads  of  the  ribs.  The  lower  arti- 
culations become,  successively,  more  moveable  than  the  upper. 

Besides  the  attachments  mentioned  as  connecting  the  carti- 
lages of  the  true  ribs  to  the  sternum,  there  is  one  superadded 
to  the  seventh  cartilage,  called  the  Costo-Xiphoid  Ligament. 
It  arises  from  the  inferior  margin  of  the  seventh  cartilage,  near 
the  sternum,  and  going  obliquely  downwards  and  inwards,  is 
inserted  into  the  anterior  face  of  the  xiphoid  cartilage,  and  has 
its  upper  fibres  running  into  the  corresponding  fibres  of  its  fel- 
low. It  is,  of  course,  placed  behind  the  rectus  abdominis  mus- 
cle, and  fills  up,  in  some  measure,  the  angle  between  the  se- 
venth cartilage  and  the  third  bone  of  the  sternum. 

At  the  surfaces  where  the  sixth  and  seventh  cartilages  come 
into  contact  by  their  edges,  also  the  seventh  and  eighth,  a  sy- 
novial  membrane  exists.  A  similar  articulation  is  sometimes 
found  between  the  fifth  and  sixth,  and  the  eighth  and  ninth  car- 
tilages, but  not  uniformly.  These  synovial  membranes  are  co- 
vered by  strong  fibres. 

It  has  been  already  stated  that  the  anterior  extremity  of  each 
of  the  first  three  cartHages  of  the  false  ribs,  is  united  by  liga- 
mentous fibres  to  the  cartilage  above.  These  ligaments  are 
strong  and  extensive,  and  give  great  solidity  to  the  common 
margin  of  the  cartilages.  The  last  two  cartilages  being  much 
smaller  than  the  others,  no  ligaments  pass  from  them;  but  they, 
with  their  ribs,  are  held  in  their  position  by  the  intercostal  and 
abdominal  muscles. 

The  cartilages  adhere  very  closely  to  their  respective  ribs, 
which  receive  them  into  the  oblong  fossa?,  at  their  anterior  ex- 
tremities. The  periosteum  of  the  rib  is  continuous  with  the 
perichondrium  of  the  cartilage,  and  the  membrane,  which  is, 
in  fact,  one  and  the  same,  adheres  very  closely  to  the  margins 
of  the  articulation;  it  is  also  re-enforced  by  some  ligamentous 
fibres  beneath  it.  No  motion  whatever  is  admitted  at  this  ar- 
ticulation. 


ARTICULATIONS  OF  THE  UPPER  EXTREMITIES.  283 


CHAPTER  VIII. 

OF  THE  ARTICULATIONS  OF  THE  UPPER  EXTREMITIES. 

' i 

Of  the  Articulations  of  the  Shoulder. 

THESE  articulations  consist  in  the  junction  of  the  clavicle  to 
the  upper  part  of  the  sternum,  and  to  the  first  rib;  of  the  scapula 
to  the  clavicle,  and  of  the  os  humeri  to  the  scapula.  . 

1.  Of  the  Sterno-Clamcular  Articulation. 

The  uneven  triangular  face  of  the  internal  end  of  the  clavicle, 
and  the  concavity  of  the  sternum,  at  its  upper  corner,  form  the 
surfaces  which  enter  into  this  articulation.  The  first  is  much 
more  extensive  than  the  articular  surface  of  the  sternum,  pro- 
jects on  every  side  beyond  its  margins,  and  is  very  prominent 
in  case  of  extreme  emaciation.  The  two  surfaces  are  covered 
by  cartilage,  of  which  that  on  the  clavicle  is  the  thickest,  and 
serves  to  fill  up  its  inequalities;  while  the  one  on  the  sternum  is 
thin  and  smooth. 

The  joint  is  invested  by  a  thick  fibrous  capsule,  the  anterior 
portion  of  which  presents  a  strong  fasciculus  of  fibres,  somewhat 
separated  by  small  interstices.  This  portion,  called  by  some 
the  radiated  ligament,  arises  from  the  anterior  extremity  of  the 
clavicle,  and,  going  downwards  and  inwards,  is  inserted  into 
the  margin  of  the  articular  cavity  of  the  sternum.  It  is  placed 
just  behind  the  origin  of  the  sterno-cleido  mastoid  muscle.  The 
capsular  ligament  is  also  strengthened  on  its  posterior  surface 
by  additional  fibres,  not  so  distinct  as  the  preceding,  but  ob- 
taining the  name  of  the  posterior  ligament. 

Of  the  Inter-Clavicular  Ligament,  (Lig.  Inter-Claviculare.) — 
Closely  connected  with  the  capsule  of  the  preceding  joint,  this 


284  SKELETON. 

ligament  is  placed  on  the  superior  end  of  the  sternum,  and  ex- 
tends from  the  internal  end  of  one  clavicle  to  that  of  the  other. 
It  is  flat  before  and  behind,  thin  and  narrow,  is  blended  with 
the  contiguous  ligamentous  structure  of  the  sternum,  and  might, 
with  propriety,  be  considered  only  an  appendage  to  the  capsu- 
lar  ligaments,  or  a  process  sent  between  them.  In  front  it 
corresponds  with  the  integuments,  and  behind  with  the  sterno- 
hyoid  muscles. 

Of  the  Inter-Articular  Cartilage. -~- When  the  capsule  of  the 
joint  is  cut  open,  this  is  brought  into  view.  It  separates  the 
bones  completely  from  each  other  by  its  extent,  and  supplies  by 
its  shape  the  want  of  correspondence  in  their  articular  faces. 
It  is  thicker  above  than  below;  its  centre  is  thin,  and  sometimes 
perforated.  Its  margins  adhere  closely  to  the  capsular  ligament; 
it  is  also  fixed  by  adhesion  to  the  upper  posterior  margin  of  the 
surface  of  the  clavicle,  and  below  to  the  union  of  the  sternum 
with  the  first  rib;  in  consequence  of  which  it  has  but  little  mo- 
tion, and  in  luxations  must  be  lacerated.  Its  structure  is  fibro- 
cartilaginous. 

Of  the  Synovia!  Membranes. — There  are  two  of  these,  one  on 
each  side  of  the  inter-articular  cartilage;  in  consequence  of 
which,  a  double  cavity  exists  in  this  articulation,  excepting  the 
cases  where  the  cartilage  is  perforated.  These  membranes^ 
contain  but  little  synovia:  they  adhere  closely  to  the  adjoining 
surfaces,  and  cannot  be  made  very  distinct,  except  in  points 
where  there  are  small  interstices  in  the' capsule,  when,  by  press- 
ing the  bones  strongly  together,  they  protrude  in  little  vesicles. 

Of  the  Costo-Clavicular  Articulation. — It  consists  in  a  short 
fasciculus  of  ligamentous  fibres,  frequently  called  the  Rhomboid 
Ligament,  which,  arising  from  the  upper  surface  of  the  cartilage 
of  the  first  rib,  ascends  obliquely  outwards,  and  is  implanted  into 
the  roughness  on  the  inferior  face  of  the  clavicle,  near  its  sternal 
end.  Its  fibres  are  parallel,  all  oblique,  and  longer  at  its  external 
than  at  its  internal  margin.  It  corresponds  in  front  with  the 
origin  of  the  subclavius  muscle,  and  behind  with  the  subclavian 
vein.  It  has  for  its  object  the  strengthening  of  the  junction  of 
the  clavicle  with  the  sternum. 


ARTICULATIONS  OF  THE  UPPER  EXTREMITIES.  285 


2.   Of  the  Scapulo-Clavicular  Articulations. 

These  exist  at  three  places;  the  first  by  a  junction  between 
the  acromion  scapulae  and  the  external  end  of  the  clavicle;  and 
the  last  two  by  ligaments  sent  from  the  coracoid  process  to  the 
under  surface  of  the  clavicle. 

The  Acromio-Clavicular  Articulation  presents,  on  each  bone, 
a  small  oblong  face,  covered  with  cartilage.  The  fibrous  cap- 
sule which  invests  it  is  very  strong  and  thick,  so  as  to  give  the 
appearance  of  a  much  greater  extent  to  the  articular  faces  of 
the  bones  than  really  exists.  This  capsule  is  strengthened  by 
additional  fibres  on  its  upper  surface,  passing  from  one  bone  to 
the  other,  and  sometimes  called  the  superior  ligament:  they  are 
parallel  to  each  other,  and  somewhat  blended  with  the  tendi- 
nous fibres  of  the  deltoid  and  trapezius  muscles.  The  capsule 
is  also  strengthened  on  its  lower  face,  by  additional  fibres,  con- 
stituting the  inferior  ligament;  they  are  not  so  abundant  as  the 
superior,  and  pass  from  the  margin  of  one  bone  to  that  of  the 
other,  after  the  same  manner.  A  synovial  membrane  is  reflect- 
ed over  these  articular  surfaces,  and  contains  but  a  very  small 
quantity  of  fluid.  In  some  instances,  an  inter-articular  fibro- 
cartilage  is  found  in  this  joint;  as  in  the  sterno-clavicular;  in 
such  case  there  is  a  double  synovial  membrane. 

Of  the  Coraco-Clavicular  Ligament.— -This  ligament  is  double, 
one  part  being  called  the  Conoid  (Lig.  Conoides,)  and  the  other, 
the  Trapezoid  (Lig.  Trapezoides.)  It  arises  from  the  roughness 
at  the  root  of  the  coracoid  process,  and  is  attached  to  the  under 
surface  of  the  clavicle.  The  conoidal  portion,  having  its  base 
upwards,  is  inserted  into  the  tubercle,  near  the  external  end  of 
the  clavicle.  Its  fibres  are  compact,  strong,  and  diverging.  The 
trapezoid  is  placed  at  the  acromial  side  of  the  other.  It  is  qua- 
drilateral, longer,  broader  and  thinner  than  the  other,  having  its 
fibres  separated  by  small  interstices;  and  arising  also  from  the 
root  of  the  coracoid  process,  it  is  inserted  into  an  oblique  line 
leading  from  the  tubercle  of  the  clavicle  to  its  acromial  end. 
The  union  of  these  two  portions  behind  forms  a  projecting  angle; 
in  front  there  is  a  depression  between  them  filled  with  fat  and 


286  SKELETON. 

cellular  substance,  also  a  bursa  mucosa.  These  ligaments  are 
bounded  in  front  by  the  subclavius,  and  behind  by  the  trapezius 
muscle. 

The  Bifid  Ligament  (Lig amentum  Bicorne)  is  placed  in  front 
of  the  subclavius  muscle.  It  arises  from  the  root  of  the  cora- 
coid  process,  at  the  sternal  side  of  the  conoid  ligament;  and 
proceeding  with  but  little  elevation,  inwards  and  upwards,  in- 
creases in  breadth  and  bifurcates.  The  superior  horn  is  in- 
serted along  the  under  margin  of  the  clavicle,  to  near  the  rhom- 
boid or  costo-clavicular  ligament;  but  the  lower  one  goes  to 
the  end  of  the  first  rib,  under  the  tendon  of  the  subclavius  mus- 
cle. This  ligament  is  a  sort  of  fascia  placed  over  the  subclavius 
muscle,  to  bind  and  strengthen  it.*  Some  of  the  fibres  of  the  su- 
perior horn  sometimes  proceed  farther,  and  leaving  the  clavicle, 
go  with  the  rhomboid  ligament  into  the  cartilage  of  the  first 
rib.t 

The  Coracoid  Ligament  (Lig.  Coracoideum)  stretches  across 
the  notch  on  the  superior  costa  of  the  scapula,  and  converts  it 
into  a  foramen.  It  runs  from  the  posterior  margin  of  the  notch 
to  the  base  of  the  coracoid  process,  and  has  some  of  its  fibres 
blending  with  the  conoid  ligament.  It  consists  of  a  small  fasci- 
culus of  fibres,  and  is  of  very  little  consequence,  excepting  in  its 
relation  to  the  superior  scapular  vessels  and  nerves. 

The  Triangular  Ligament  (Coraco-Acromialis)  of  the  Scapula, 
as  its  name  implies,  extends  from  the  coracoid  to  the  acromion 
process  above  the  shoulder  joint.  It  arises  from  nearly  the 
whole  superior  margin  of  the  coracoid  process,  in  two  divisions, 
separated  partially  by  cellular  tissue.  Its  fibres  converge  in 
their  progress,  by  which  it  becomes  thicker,  and  is  inserted  into 
the  point  of  the  acromion  process,  just  beneath  its  junction 
with  the  clavicle.  This  ligament  is  covered  by  the  deltoid  mus- 
cle and  the  clavicle,  and  has  the  supra-spinatus  beneath  it.  Its 
anterior  margin  is  continuous  with  a  condensed  cellular  mem- 
brane beneath  the  deltoid. 

*  This  ligament  is  called  the  clavicular  fascia  by  M.  M.  Velpeau  and  Blandin, 
in  their  treatises  on  surgical  anatomy, 
f  Caldani,  Plate  XLI. 


ARTICULATIONS  OF  THE  UPPER  EXTREMITIES.  287 


Of  the  Scapula-Humeral  Articulation. 

The  glenoid  cavity  of  the  scapula,  and  the  head  of  the  os 
humeri  form  this  joint.  As  usual,  each  articular  surface  is 
covered  with  cartilage,  of  which  that  on  the  os  humeri  is  thick- 
er in  the  middle  than  near  its  circumference,  while  the  reverse 
occurs  on  the  scapula.  From  the  shallowness  of  the  glenoid 
cavity  and  the  much  greater  size  of  the  head  of  'the  os  humeri, 
but  very  few  points  of  their  opposed  surfaces  can  come  into 
contact  at  the  same  moment,  though  they  may  all  do  so  in  suc- 
cession: hence,  a  considerable  portion  of  the  head  of  the  os  hu- 
meri is  always  against  the  capsule  of  the  joint.  The  remaining 
parts  of  this  articulation  are  the  capsular  ligament,  the  synovia! 
membrane,  and  the  glenoid  ligament. 

The  capsular  ligament  invests  completely  this  joint,  though  it 
is  thinner  in  some  places  than  at  others.  It  arises  from  the  mar- 
gin of  the  glenoid  cavity,  and  is  inserted  into  the  neck  of  the  os 
humeri,  including  a  larger  space  of  the  neck  below,  than  it  does 
above.  The  tendons  of  the  muscles  whrich  arise  from  the  ex- 
ternal and  internal  surface  of  the  scapula,  to  be  inserted  into 
the  tuberosities  of  the  os  humeri,  as  they  approach  their  points 
of  insertion  adhere  very  closely  to  the  capsular  ligament,  and 
are,  indeed,  more  or  less  blended  with  it.  Bichat'  considers, 
that  the  tendon  of  the  sub-scapularis  muscle  supplies  the  place 
of  the  capsular  ligament  entirely  at  its  lower  part.  This  liga- 
ment is  formed  by  fibres,  which  are  very  much  intermixed  with 
one  another,  arid  have  a  greater  degree  of  thickness  above  than 
below,  or,  indeed,  at  any  other  point.  The  former  is  due  to  a 
thick  fasciculus,  the  Coraco-Humeral  Ligament,  also  called  by 
some  Ligamentum  Adscititium,  which  takes  its  origin  from  the 
posterior  and  external  margin  of  the  coracoid  process,  and  pro- 
ceeding beneath  the  triangular  ligament  to  the  upper  part  of  the 
os  humeri,  joins  the  capsular  ligament,  and  adheres  very  firmly 
to  it.  This  ligament  keeps  the  head  of  the  os  humeri  on  its 
proper  level  in  regard  to  the  glenoid  cavity;  but  the  moment  it 
is  cut,  the  length  of  the  capsular  ligament  permits  the  head  of 
the  os  humeri  to  fall  about  an  inch,  and,  indeed,  to  suffer  a  par- 
tial dislocation.  The  strength  of  the  joint  however  depends 


288  SKELETON. 

essentially  upon  the  muscles  which  surround  it,  as  the  deltoid, 
supra-spinatus,  infra-spinatus,  teres  minor,  sub-scapularis,  long 
head  of  triceps,  and  some  others,  which  are  farther  removed 
from  it. 

The  synovial  membrane  is  a  perfect  sac,  which  covers  the 
glenoid  cavity,  the  internal  face  of  the  capsular  ligament,  and 
the  neck  and  head  of  the  os  humeri.  On  the  lower  part  of  the 
neck  it  is  reflected  over  some  small  fatty  masses,  commonly  called 
glands.  Just  beneath  the  root  of  the  coracoid  process,  from  there 
being  a  deficiency  of  the  capsular  ligament,  the  synovial  mem- 
brane covers  the  articular  side  of  the  tendon  of  the  sub-scapu- 
laris, and  is  reflected  for  ten  or  twelve  lines,  between  it  and  the 
scapula,  forming  a  sort  of  pouch,  resembling  a  bursa  mucosa. 

The  tendon  of  the  biceps  muscle  runs  through  this  articulation 
from  the  superior  end  of  the  glenoid  cavity.  The  cavity  itself  is 
deepened  by  a  fibrous  margin  all  around,  called  the  glenoid  liga- 
ment; a  considerable  part  of  whose  fibres  may  be  traced  from 
the  tendon  of  the  biceps  by  its  bifurcating.  The  tendon  is  bound 
down  in  the  bicipital -groove  by  fibres  passing  from  one  to  the 
other  of  the  bony  margins,  and  which  may  be  considered  a 
continuation  of  the  capsular  ligament.  As  the  tendon  is  about 
emerging  from  the  groove  at  the  lower  margin  of  the  tuberosi- 
ties,  the  synovial  membrane  which  lines  the  groove  thus  far,  is 
reflected  from  it,  to  the  surface  of  the  tendon,  and  continues  to 
cover  and  enclose  it  up  to  the  origin  at  the  glenoid  cavity.  It  is 
thus  evident  that  though  the  tendon  passes  through  the  joint, 
the  cavity  of  the  synovial  membrane  is  kept  entire. 


Of  the  Elbow  Joint. 

This  articulation  is  formed  by  the  lower  end  of  the  os  hu- 
meri and  the  upper  end  of  the  ulna  and  of  the  radius.  The  ar- 
ticular faces  which  were  described  in  the  account  of  these 
bones  are  covered,  as  usual,  with  cartilage,  the  particular  ar- 
rangement of  which  will  be  presently  pointed  out.  A  strong 
capsular  ligament,  an  annular  or  coronary  ligament,  and  a  syno- 
vial membrane,  hold  these  several  bones  together. 

The  Capsular  Ligament  invests  completely  the  articular  ex- 


ARTICULATIONS  OF  THE  UPPER  EXTREMITIES.  289 

tremities  of  these  bones,  and  conceals  them  from  view.  It  is 
attached  to  the  sides  of  the  os  humeri  at  the  lower  part  of  its 
condyles  near  the  articular  surface ;  but  in  front  it  arises  some 
distance  from  the  articular  face  at  the  upper  margins  of  the  lit- 
tle cavities,  for  the  head  of  the  radius  and  for  the  coronoid  pro- 
cess of  the  ulna:  behind,  it  arises  in  like  manner  from  the  upper 
margin  of  the  cavity  for  receiving  the  olecranon  process  ;  so 
that  the  depressions,  both  before  and  behind,  are  included  with- 
in the  circumference  of  the  articulation.  The  lower  part  of 
the  capsular  ligament  is  inserted  into  the  margin  of  the  articu- 
lar surface  of  the  ulna,  all  around*,  including,  also,  the  whole  of 
the  head  of  the  radius,  and  the  upper  part  of  its  neck. 

This  capsule  is  strengthened  very  much  at  particular  points, 
and  as  the  joint  is  hinge-like,  the  strengthening  is  more  abun- 
dant at  its  sides,  constituting  lateral  ligarnexits. 

The  external  Lateral,  or  the  Brachio  Radial  Ligament,  (Lig. 
Cubiti  Externum,)  is  connected  above  to  the  lower  part  of  the 
external  condyle,  and  is  fixed  below  into  the  annular  ligament 
which  surrounds  the  neck  of  the  radius.  It  is  very  much  con- 
founded with  the  tendinous  mass  common  to  the  muscles  at  this 
part  of  the  arm,  more  particularly  that  of  the  supinator  radii 
brevis.  It  is  a  round  fasciculus  of  parallel  and  condensed  fibres, 
spreading  somewhat  below  into  the  annular  or  orbicular  liga- 
ment. The  Internal  Lateral  or  the  Brachio  Ulnar  Ligament, 
(Lig.  Cubiti  Iriternum)  arises  from  the  lower  part  of  the  inter- 
nal condyle,  and  spreading  out  so  as  to  assume  a  triangular 
shape,  divides  into  two  portions,  one  of  which  is  inserted  into 
the  internal  margin  of  the  coronoid  pfocess  of  the  ulna,  and  the 
other  into  the  internal  margin  of  the  olecranon  process.  It  also 
is  much  blended  with  the  tendons  of  the  muscles  which  lie  over 
it.  Intermediately  to  the  lateral  ligaments,  both  before  and  be- 
hind, the  fibrous  structure  of  the  capsular  ligament  is  very  dis- 
tinct, but  thin,  in  order  to  accommodate  the  motions  of  the 
joint;  some  of  the  fibres  are  insulafed,  and  have  interstices  be- 
tween them  filled  with  fat.  Some  of  these  fibres  are  oblique, 
and  others  straight:  they  are  called,  generally,  accessory  liga- 
ments. 

The  Coronary  Ligament  of  the  Radius  (Lig.  Radii  Orbiculare) 
VOL.  I.— 25 


290  SKELETON. 

is  brought  more  distinctly  into  view  by  cutting  open  the  joint.  It 
is  then  seen  to  arise  from  the  anterior  margin  of  the  lesser  sig- 
moid  cavity  of  the  ulna,  and  surrounding  two-thirds  of  the  neck 
of  the  radius,  to  be  inserted  into  the  posterior  margin  of  the  same 
cavity.  Jtis  a  strong,  flat,  narrow  fasciculus,  the  fibres  of  which 
go  in  a  circular  direction.  Its  superior  margin  is  blended  with  the 
external  lateral  ligament;  its  inferior  margin  fs  loose,  being  con- 
nected with  the  lower  part  of  the  neck  of  the  radius  only  by  a 
reflection  of  the  synovial  membrane,  with  the  exception  that  a 
few  fibres  pass  from  it  behind,  to  the  contiguous  part  of  the  ulna. 
Its  density  is  very  considerable,  sometimes  almost  cartilaginous. 

The  Synovial  Membrane  lines  the  whole  internal  face  of  the 
capsular  ligament,  from  which  it  is  separated  behind  by  a  large 
mass  of  fat  in  the  olecranon  depression  of  the  os  humeri,  and  in 
front  by  another  mass  in  the  coronoid  depression.  A  small 
circular  ridge  of  fat  also  projects  into  the  joint  around  the  head 
of  the  radius,  and  there  is  another  at  the  internal  margin  of  the 
olecranon.  The  object  of  these  masses  seems  to  be  to  fill  up 
the  partial  vacancies  which  exist  between  the  articular  faces 
of  the  bones,  and  they  are  all  so  directed  by  their  attachment 
to  the  capsular  ligament,  as  to  be  preserved  from  being  pinched. 
The  synovial  membrane  is  also  reflected  from  the  capsular  li- 
gament to  the  articular  faces  of  the  bones,  so  as  to  line  the  se- 
veral depressions  on  the  os  humeri,  and  to  include  the  neck  of 
the  radius. 

The  head  of  the  radius  is  completely  invested  with  cartilage. 
The  greater  sigmoid  cavity  of  the  ulna  has  the  cartilage  sepa- 
rated transversely  into  two  portions,  by  a  small  mass  of  fat 
traversing  its  bottom.  The  cartilage  elsewhere  is  uniformly 
spread  over  the  articular  surfaces  of  the  bones. 

Of  the  Literosseal  Ligament,  (Membrana  Interossea.} — It  fills 
up  the  space  between  the  two  bones  of  the  fore  arm  almost  en- 
tirely, by  commencing  just  below  the  tubercle  of  the  radius 
and  ending  near  the  wrist.  It  consists  in  oblique  and  parallel 
fibres,  which  pass  from  the  ulnar  edge  of  the  radius  downwards 
to  the  radial  edge  of  the  ulna.  It  is  thin,  but  extremely  strong, 
bein^  covered  in  front  by  the  flexor  muscles;  and  behind  by  the 


ARTICULATIONS  OF  THE  UPPER  EXTREMITIES.  291 

extensors,  and,  as  Mr.  Boyer  observes,  seems  to  be  intended 
rather  to  afford  origin  to  muscles  than  to  unite  the  bones.  Its 
superior  part  is  thinner  above,  and  a  large  opening  exists  there 
for  the  passing  of  the  interosseal  vessels  to  the  back  of  the  fore 
arm.  Its  inferior  part,  is  thicker,  where  openings  also  exist, 
but  small,  for  the  passing  of  vessels.  There  are  some  other 
smaller  perforations  in  this  ligament,  but  of  less  note  than  the 
preceding,  also  for  vessels.  On  its  posterior  face  there  are  one 
or  two  bands,  the  fibres  of  which  decussate  the  other  fibres. 

Beside  the  interosseal  ligament,  there  is  one  called  round 
(Teres,)  situated  obliquely  between  the  two  bones  at  the  upper 
part  of  the  interval  which  separates  them.  It  arises  from  the 
base  of  the  coronoid  process,  just  below  the  insertion  of  the 
brachialis  internus;  and  descending  obliquely  outwards,  is  in- 
serted into  the  radius  below  its  tubercle.  Its  object  is  to  bind 
the  bones  together,  at  a  point  which  is  weakened  by  the  defi- 
ciency of  the  interosseal  ligament.  This  deficiency  is,  in  fact, 
much  larger  than  the  simple  passing  of  the  vessels  requires; 
for  it  is  also  large  enough  to  allow  the  tubercle  of  the  radius  to 
rotate  freely,  a  motion  which  would  have  been  checked  by  the 
presence  of  the  ligament. 

Of  the  Articulations  of  the  Wrist. 

Several  articular  cavities  present  themselves  at  this  point. 
One  is  between  the  lower  part  of  the  ulna  and  the  radius,  ano- 
ther between  the  carpal  bones  and  those  of  the  fore  arm,  and 
a  third  between  the  two  rows  of  carpal  bones.  One  general 
capsule  invests  these  parts. 

1.  The  Lower  Radio-Ulnar  Articulation — is  surrounded  by  a 
section  of  the  fibres  belonging  to  the  general  capsular  ligament 
of  the  wrist:  their  attachment,  however,  is  so  loose,  that  they 
allow  the  bones  to  rotate  freely  upon  each  other,  besides  which 
they  are  not  so  abundant  as  in  other  places.  When  this  joint 
is  cut  open,  it  will  be  seen  that  the  head  of  the  ulna  is  covered 
with  cartilage,  and  that  the  cartilage  which  covers  the  carpal 
articular  face  of  the  radius,  projects  between  the  ulna  and  the 
os  cuneiforme;  and  covers  also  the  sigmoid  cavity  of  the  radius; 
so  that  a  cavity  for  receiving  the  convex  head  of  the  ulna  is 


292  SKELETON. 

formed  by  the  cartilage  of  the  radius.  The  margins  of  this 
projecting  point  of  the  radial  cartilage  are  fibrous,  which  has 
induced  the  French  anatomists  to  speak  of  it  under  the  name 
of  triangular  ligament.  It  is,  in  fact,  an  inter-articular  fibro- 
cartilage,  and  is  said  to  be  occasionally  .detached  from  the  ra- 
dius, but  I  have  not  seen  it  in  that  state:  ite  centre  not  unfre- 
quently  is  perforated,  so  that  a  communication  exists  between 
this  joint  and  the  next  of  the  wrist.  Its  margins  adhere  very 
closely  to  the  capsular  ligament,  and  its  point  is  fixed  into  the 
depression  which  separates  the  styloid  process  of  the  ulna  from 
its  head.  The  synovial  membrane  which  lines  this  cavity  is 
unusually  loose,  both  before  and  behind,  in  consequence  of  the 
great  motion  of  the  bones:  it  is  also  very  loose  above.  This 
joint  is  sometimes  called  the  Sacciform,  from  its  looseness. 

2.  Of  the  Radio-Carpal  Articulation. — The  radius  above,  and 
the  scaphoides,  lunare,  and  cuneiforme  below,,  form  the  basis  of 
this  articulation.  An  oblong,  elliptical  cavity,  the  ulnar  extre- 
mity of  which  is  made  by  the  projection  of  the  cartilage  of  the 
radius,  receives  the  convexity  of  the  bones  of  the  wrist.  The 
scaphoides  and  the  lunare  come  in  contact  with  the  radius, 
while  the  cuneiforme  rests  against  the  projecting  cartilage. 
There  is  a  slight  elevation  of  the  radial  cartilage  opposite  to 
the  interstice  between  the  first  two  bones.  The  oblong  ellipti- 
cal cavity  is  filled  by  a  corresponding  head,  on  the  part  of  the 
bones  of  the  carpus  just  enumerated.  Each  of  the  latter  bones, 
in  a  fresh  state,  is  covered  by  its  appropriate  cartilage.  The 
cartilages  are  connected,  or  rather  continued  into  one  another, 
by  a  narrow  fibro-cartilaginous  substance  placed  at  the  margin 
of  the  interstice  between  these  bones.  This  substance  sepa- 
rates the  cavity  of  the  radio-carpal  articulation  from  that  of  the 
proper  carpal  articulation. 

The  Capsular  Ligament  arises,  before  and  behind,  around 
the  margin  of  the  articular  face  of  the  bones  of  the  fore  arm, 
from  the  styloid  process  of  the  radius  to  that  of  the  ulna,  ad- 
hering very  closely  to  the  margins  of  the  fibro-cartilage  insi- 
nuated between  the  ulna  and  the  cuneiforme.  It  is  inserted 
below7,  into  the  circumference  of  the  head  formed  by  the  sca- 
phoides, lunare,  and  cuneiforme,  though  many  of  its  fibres  may 


ARTICULATIONS  OF  THE  UPPER  EXTREMITIES.  293 

be  traced  to  the  bones  of  the  second  row.  It  is  a  loose  and 
thin  membrane,  the  fibrous  fasciculi  of  which  leave  interstices 
at  several  points  between  them,  through  which  the  synovial 
membrane  may  be  seen.  The  capsular  ligament  is  strengthened 
at  particular  places,  by  additional  fasciculi  of  fibres  having  ap- 
propriate names.  For  example,  the  internal  lateral  ligament 
arises  from  the  styloid  process  of  the  ulna,  and  is  inserted  into 
the  cuneiforme,  some  of  its  fibres  being  extended  to  the  ante- 
rior annular  ligament,  and  to  the  pisiforme.  The  external  la- 
teral ligament  arises  from  the  styloid  process  of  the  radius,  and 
is  inserted  into  the  radial  end  of  the  scaphoides;  some  of  its 
fibre?  being  continued  on  to  the  trapezium,  and  to  the  anterior 
annular  ligament.  The  anterior  ligament  arises  from  the  vici- 
nity of  the  styloid  process  of  the  radius,  and  passing  obliquely 
downwards  and  inwards,  is  inserted  into  the  anterior  face  of 
the  scaphoides,  lunare,  and  cuneiforme.  Its  fibres  are  not  very 
evident  or  well  marked.  The  posterior  ligament  is  not  so 
broad  as  the  last,  and  is  more  distinct.  It  also  arises  from  the 
radius,  by  and  near  its  styloid  process,  and  descending  oblique- 
ly inwards,  is  inserted  into  the  lunare  and  cuneiforme.  The 
last  two  ligaments  have  no  connexion  with  the  ulna,  the  rota- 
tion of  the  fore  arm  is,  therefore,  unimpeded  by  them. 

The  synovial  membrane  of  the  radio-carpal  articulation  is 
displayed  on  the  articular  faces  af  the  bones  and  their  interme- 
diate fibre-cartilage,  and  lines  the  internal  face  of  the  capsular 
ligament.  When  the  joint  is  pressed  upon,  this  membrane  is 
protruded,  in  the  form  of  little  vesicles,  in  the  interstices  be- 
tween the  fasciculi  of  the  capsular  ligament.  A  fold  of  it  con- 
taining a  small  quantity  of  adipose  matter  is  observed  on  the 
back  of  the  cavity  of  the  joint,  passing  from  the  junction  of  the 
scaphoides  and  lunare  to  the  corresponding  point  of  the  radius; 
it  is  the  ligamentum  mucosum  of  some  writers. 

3.  Of  the  Articulation  between  the  two  rows  oftfie  Carpal  Bones. 
—The  scaphoides,  lunare,  and  cuneiforme  of  the  first  row,  and 
all  the  bones  of  the  second  row,  are  the  foundation  of  this  joint, 
the  surfaces  of  which  have  been  described  already.  These 
surfaces  are  covered  with  cartilage,  each  bone  having  its  ap- 
propriate cartilage,  which  is  continued  on  its  side  where  the 

25* 


294  SKELETON. 

bone  touches  the  adjacent  one.     The  joint  is  furnished  with  a 
capsular  ligament  and  a  synovial  membrane. 

The  Capsular  Ligament  surrounds  the  articulation,  passing 
on  every  side  from  the  upper  lo  the  lower  row,  and  adhering 
strongly  to  the  bones.  It  is  in  a  great  degree  a  continuation 
of  the  capsule  of  the  radio-carpal  joint,  and  has,  at  the  same 
points,  an  increase  of  thickness,  called  after  the  same  names. 
The  internal  lateral  ligament  is  attached  by  one  end  to  the  cu- 
neiforme,  and  by  the  other  to  the  side  of  the  unciforme.  The 
external  lateral  ligament  arises  from  the  extremity  of  the  sca- 
phoides,  and  is  inserted  into  the  side  of  the  'trapezium.  The 
posterior  and  anterior  ligaments  have  the  course  of  their  fibres 
more  distinctly  seen  on  the  side  of  the  synovial  membrane. 
The  first  consists  in  many  fibres  arising  from  the  bones  of  the 
first  row  and  going  to  the  second  row;  its  fibres  are  shorter 
and  more  compact.  The  anterior  arises  and  is  inserted  after 
the  same  way,  some  of  them  terminating  in  the  anterior  liga- 
ments of  the  hand. 

The  Synovial  Membrane  is  not  only  displayed  on  the  oppo- 
site surfaces  of  the  two  carpal  rows,  but  also  is  reflected  upoft 
the  lateral  faces  of  the  bones  belonging  to  each  row.  It,  there- 
fore, sends  processes,  two  of  which  are  found,  above;  one  be- 
ivveen  the  scaphoides  and  the  lunare,  and  the  other  between 
the  lunare  and  cuneiforme.  These  processes  are  arrested  at 
their  upper  extremities  by  the  fibro-cartilaginous  matter  be- 
tween the  bones,  which  was  spoken  of  in  the  radio-carpal  ar- 
ticulation. It  also  sends  three  processes  downwards,  one  be- 
tween the  trapezium  and  the  trapezoides.  another  between  the 
latter  and  the  magnum,  and  the  third  between  the  magnum  and 
the  unciforme.  Those  latter  processes  communicate  with  or 
are  continuous  with  the  synovial  membrane,  between  the  car- 
pal and  the  metacarpal  bones  of  the  fingers.*  The  connexions 
and  reflections  of  this  membrane  are  of  the  greatest  impor- 
tance, as  they  form  a  commonieation  from  the  top  of  the  wrist 
to  the  base  of  the  metacarpal  bones;  not  only  covering  the  ar- 
ticular surfaces,  but  being  prolonged  in  some  instances  beyond 

*  Eicliat,  Anat.  Dcscr 


ARTICULATIONS  OF  THE  UPPER  EXTREMITIES.  295 

them,  as  on  the  back  of  the  os  magnum,  where  it  answers  as 
a  periosteum. 

In  addition  to  the  articulation  just  described,  between  the 
two  rows  of  carpal  bones,  the  individual  bones  of  each  row  have 
particular  fastenings  of  ligarnentous  fibres,  which  run  trans- 
versely from  the  margin  of  one  bone  to  the  margin  of  the  next. 
These  fibres,  from  their  position,  are  called  dorsal  and  palmar 
ligaments.  The  upper  row  has  one  dorsal  ligament  between 
the  scaphoid  and  lunar,  and  another  between  the  latter  and  the 
cuneiform — it  has  in  the  same  way  two  palmar  ligaments  on 
its  front  surface.  The  lower  row  has,  after  the  same  plan, 
three  dorsal  and  three  palmar  ligaments  between  its  bones. 
These  several  ligaments  are  best  seen  on  the  side  of  the  syno- 
vial  membrane,  as  externally  their  fibres  are  very  much  mixed 
with  those  of  the  capsular  ligament.  It  is  obvious  that  they 
are  highly  useful  in  preventing  the  bones  from  sliding  laterally 
on  each  otherj,  except  to  a  small  extent. 

The  Pisiform  Bone  has  an  articulation  with  the  cuneiform 
completely  distinct  from  any  other.  The  articular  faces  of 
this  joint  are  covered  with  cartilage  and  invested  by  a  synovial 
membrane  and  a  capsular  ligament,  which  allow,  from  their 
looseness,  considerable  motion.  The  capsule,  though  general- 
ly thin,  is  strengthened  by  accessory  fibres,  which  are  well 
marked  below.  These  fibres  arising  from  the  inferior  extremi- 
ty of  the  pisiform,  some  of  them  are  attached  to  the  extremity 
of  the  unciform  process  of  the  os  unciforme,  and  others  to  the 
base  of  the  fifth  metacarpal  bone.  The  insertion  of  the  tendon 
of  the  flexor  carpi  ulnaris  answers  as  a  ligament  to  this  bone 
above,  and  there  is  a  very  strong  fasciculus  of  ligament,  passing 
from  the  pisiforme  to  the  end  of  the  unciform  process,  and  by 
that  means  conveying  the  action  of  the  flexor  ulnaris  to  it.  It 
has  but  little  motion  from  above  downwards,  and  a  good  deal 
laterally. 

Of  the  Carpo-Metacarpal  Articulations. 

The.  bony  articular  surfaces,  here,  as  well  as  all  the  others, 
of  the  hand,  have  been  sufficiently  described  and  are  in  the  recent 
state  covered  with  cartilage.  It  will  therefore  be  unnecessary 
to  renew  the  observations  on  these  subjects., 


296  SKELETON. 

The  first  of  these  articulations,  or  that  of  the  metacarpal 
bone  of  the  thumb,  with  the  trapezium,  is  much  more  movea- 
ble  than  any  of  the  others,  and  presents  some  peculiarities.  It 
is  entirely  distinct,  slightly  removed  from  the  next,  and  is  sur- 
rounded by  a  capsule  which  is  attached  by  its  ends  to  the  ar- 
ticular margins  of  the  bones.  This  capsule  is  strengthened  by 
additional  fibres,  which  are  particularly  distinct  and  abundant, 
posteriorly  and  externally.  The  synovial  membrane  is  dis- 
played, as  usual,  on  the  internal  face  of  the  capsule,  and  over 
the  articular  faces. 

The  other  four  metacarpal  bones  are  articulated  as  follows: 
The  second  one  is  joined  to  the  trapezoides,  trapezium,  and  mag- 
num— the  third  unites  to  the  magnum  alone — the  fourth  to  the 
unciform,  with  a  small  portion  of  the  magnum — and  the  fifth 
to  the  nnciform.  The  ligaments  are  placed  before  and  behind, 
and  may  also  be  termed  dorsal  and  palmar. 

The  dorsal  ligaments  descend  from  the  carpal  to  the  metacar- 
pal bonjes.  The  second  metacarpal  bone  receives  two  ligaments, 
one  from  the  trapezium,  and  another  from  the  trapezoides — 
the  third  receives  one  from  the  rnagnum — the  fourth  receives 
two,  one  from  the  magnum,  and  the  other  from  the  unciform — 
the  fifth  receives  one  from  the  unciform.  Transverse  fibres 
pass  between  these  dorsal  ligaments  to  connect  the  bases  of  the 
metacarpal  bones. 

The  palmar  ligaments  are  arranged  on  a  plan  corresponding 
with  that  of  the  dorsal ;  but,  from  the  length  of  their  superficial 
fibres,  are  not  so  distinct  from  each  other.  Transverse  fibres 
pass  also  between  the  metacarpal  bones  of  the  fingers  at  their 
base,  and  form  interosseous  ligaments  which  keep  them  to- 
gether. 

The  articulations  thus  formed  and  held  together,  are  covered 
by  two  synovial  membranes,  being  processes  from  that  between 
the  two  rows  of  carpal  bones.  One  of  these  processes,  sent  down 
between  the  trapezoides  and  the  magnum,  displays  itself  over 
the  inferior  surface  of  these  bones  and  the  head  of  the  metacar- 
pal bone  of  the  fore  and  of  the  middle  finger.  The  second  pro- 
cess which  is  sent  down  between  the  magnum  and  the  unciforme, 
is  reflected  over  the  two  last  carpo-metacarpal  articulations. 
These  processes  have  a  septum  between  them,  at  the  ulnar  side 


ARTICULATIONS  OF  THE  UPPER  EXTREMITIES.  297 

of  the  base  of  the  third  metacarpal  bone,  and  do  not  communi- 
cate with  each  other,  except  through  the  proper  carpal  articu- 
lation. The  specification  of  this  arrangement  is  overlooked  by 
anatomists  generally. 

The  Inferior  Palmar  Ligaments  are  three  in  number,  and  are 
between  the  lower  ends  of  the  metacarpal  bones  of  the  fingers, 
each  one  consists  in  a  transverse  fasciculus,  placed  between  the 
flexor  tendons  and  the  interosseous  muscles,  and  on  a  level 
with  the  anterior  part  of  the  first  joint  of  the  fingers.  Their 
more  superficial  fibres  may  be  traced  across  the  bones,  and  are 
somewhat  blended  with  the  capsular  ligaments;  the  more  deep- 
seated  are  short,  and  pass  from  one  bone  to  the  other. 


Of  the  Metacarpo-Phalangial  Articulations. 

These  are  formed  by  the  lower  ends  of  the  metacar.pal  bones, 
and  the  upper  ends  of  the  first  phalanges.  Each  one  presents 
an  anterior  ligament,  two  lateral  ones,  and  a  synovial  mem- 
brane. 

The  anterior  Ligament*  is  a  flat  fibrous  semicircle,  on  the 
front  of  the  articulation,  of  considerable  thickness.  It  goes  trans- 
versely, and  has  its  two  extremities  attached  to  the  ridge  on 
either  side  of  the  articular  margin  of  the  metacarpal  bone.  Its 
inferior  margin  descends  a  little,  and  comes  in  contact  with  the 
synovial  membrane.  In  front,  many  of  its  fibres  are  obtained 
from  the  ligamento-cartilaginous  sheath  of  the  flexor  tendons, 
so  that  it  may  be  considered  as  made  by  two  planes — the  pal- 
mar one  facing  towards  the  tendons,  and  forming  the  trochlea, 
in  which  they  play,  and  the  other  being  next  to  the  joint,  and 
continued  to- the  lateral  ligaments.  The  thickness  of  the  ante- 
rior ligament,  besides  communicating  great  strength  to  the  joint 
is  useful  in  removing  the  tendons  from  the  line  of  motion  of  the 
phalanges,  and  thereby  giving  increased  power  and  delicacy  of 
motion  to  the  muscles.  Bichat  considers  himself  to  have  first 
indicated  particularly  this  structure,  which  he  thought  was  in- 
tended to  protect  the  articulation  from  the  impression  of  the  ten- 
don: he  ought  to  have  added,  in  the  firm  grasping  of  bodies,  and 
to  make  the  movements  of  the  joint  more  delicate.  On  the  sides 

*  Bichat,  loc.  cit. 


298  SKELETON.- 

of  this  ligament  belonging  to  the  thumb,  and  in  its  thickness, 
are  developed  the  sesamoid  bones. 

The  Lateral  Ligaments  are  situated  one  on  each  side.  They 
arise  from  the  sides  of  the  metacarpal  bone  behind  the  former, 
and  in  connexion  with  it,  and,  descending  obliquely  forwards,  are 
fixed  into  the  sides  of  the  upper  end  of  the  first  phalanx.  They 
are  round,  distinct,  and  strong,  and  are  formed  from  numerous 
parallel  fibres. 

The Synovial  Membrane  lines  this  articulation,being  displayed 
over  its  lateral  and  anterior  ligaments,  and  on  the  articular  faces 
of  the  bones.  It  is  reflected  on  the  metacarpal  bone,  some  little 
distance  from  the  margin  of  its  cartilage  in  front,  whereby  the 
cavity  is  enlarged,  arid  the  flexion  of  the  fingers  is  favoured.  It 
is  in  contact,  behind,  with  the  tendon  of  the  extensor  muscle, 
which  there  supplies  the  place  of  ligament. 


Of  the  Phalangial  Articulations. 

There  are  two  of  these  to  each  finger,  and  one  only  to  the 
thumb.  They  are  provided  with  an  anterior  ligament,  a  lateral 
ligament  on  each  side,  and  a  synovial  membrane. 

The  anterior  Ligament  corresponds  so  exactly  with  what  has 
been  said  in  the  preceding  article  on  the  same  structure,  that, 
with  the  exception  of  its  being  smaller,  the  description  already 
given,  will  suffice.  It  seems  to  answer,  in  every  respect,  the 
same  objects. 

The  Lateral  Ligaments,  also,  arising  from  the  sides  of  the  pha- 
lanx above,  run  downwards  and  somewhat  forwards  to  be  insert- 
ed into  the  upper  part  of  the  sides  of  the  phalanx  below. 

The  Synovial  Membrane  has  reflections  corresponding  with 
those  of  the  preceding  articulations,  with  the  addition  that  it  co- 
vers more  of  the  anterior  inferior  face  of  the  first  and  second 
phalanges.  Thus,  by  cutting  through  the  anterior  ligament, 
longitudinally,  and  turning  it  aside,  it  will  be  seen  that  the  cavity 


ARTICULATIONS  OF  THE  LOWER  EXTREMITIES.  299 

of  the  second  and  third  joints  of  the  finger  is,  by  this  reflection 
of  the  synovial  membrane,  extended  upwards  between  the  pha- 
lanx and  the  flexor  tendons  nearly  one-third  of  the  whole  length 
of  the  phalanx,*  a  circumstance  worth  attending  to  in  the  ac- 
cidents of  the  part. 


CHAPTER  IX. 


OF  THE  ARTICULATIONS  OF  THE  LOWER  EXTREMITIES. 

Of  the  llio-Femoral,  or  Hip  Articulation. 

THE  basis  of  this  articulation  is  laid  by  the  head  of  the  os  fe- 
moris  being  received  into  the  acetabulum.  Both  surfaces  are 
covered  by  thick  cartilage:  in  the  former  it  is  interrupted,  how- 
ever, by  the  depression  near  the  centre,  and  becomes  very  thin 
near  the  margin;  and,  in  the  latter,  the  cartilage  is  deficient  in 
the  whole  extent  of  the  rough  surface  at  its  lower  part.  A 
cotyloid  ligament,  a  fibrous  capsule,  the  round  or  inter-articu- 
lar ligament,  and  a  synovial  membrane,  are  moreover,  con- 
cerned in  this  joint. 

The  Cotyloid  Ligament  (Lig.  Cotyloideum)  is  a  fibrous  pris- 
matic ring  which  tips  the  margin  of  the  acetabulum,  and  there- 
by increases  its  depth;  it  can  only  be  seen  by  cutting  open  the 
capsule.  Its  thickness  is  unequal,  being  considerable  on  the 
anterior  third  of  the  circumference  of  the  acetabulum,  where 
it  assists  in  converting  the  notch  into  a  foramen,  but  not  so 
much  so  elsewhere.  Just  below  the  anterior  inferior  spinous 
process,  the  acetabular  head  of  the  rectus  femoris  sends  some 
tendinous  fibres  to  it.  Its  base  is  broader  than  its  margin,  and 
is  marked  off  from  the  articular  cartilage  by  a  line,  or  narrow 
groove,  between  them.  Its  acetabular  side  is  covered  by  the 
synovial  membrane;-  the  other  side  has  the  capsular  ligament 

*  Bichat,  loc.  cit. 


300  SKELETON. 

adhering  to  it;  and  the  third  side  adheres  to  the  bone.  Where 
it  subtends  the  notch  of  the  acetabulum,  the  cotyloid  ligament 
is  re-enforced  by  additional  ligamentous  fibres,  placed  beneath 
it,  and  going  from  the  upper  to  the  lower  end  of  the  notch. 
These  fibres  consist  of  two  planes,  one  internal  and  the  other 
external,  partly  crossing  each  other,  and  adhering  closely  to 
the  cotyloid  ligament. 

The  Inter-Articular,  or  Round  Ligament,  (Lig.  Teres,)  is  a 
true  ligamentous  band,  which  is  attached  at  the  one  end  to  the 
pit  on  the  head  of  the  os  femoris,  and  aftevwards  by  a  slight 
dissection,  is  easily  separated  into  two  fasciculi.  Of  these,  the 
lower  one  may  be  traced  to  the  inferior  end  of  the  cotyloid 
notch,  where,  winding  around  the  prominence  of  bone,  it  begins 
to  adhere  to  the  ischium,  and  continues  to  do  so  from  that 
point  along  the  anterior  face  of  the  ischium,  just  below  the 
acetabulum,  to  a  point  between  the  latter  and  the  upper  ante- 
rior part  of  the  tuber.  The  other  portion  is  directed  towards 
the  superior  end  of  the  notch,  and  is  attached  there  by  two  ex- 
tremities, one  near  the  margin  of  the  acetabulum,  and  the  other 
three  or  four  lines  from  it  within.*  The  fibres  of  the  round 
ligament  are  somewhat  intermixed  also  with  those  of  the  coty- 
loid ligament  subtending  the  notch. 

The  Capsular  Ligament  (Capsula  Fibrosa)  is  the  strongest  in 
the  body,  and  represents  a  conoidal  sac,  open  at  both  extremi- 
ties, by  which  it  adheres  to  the  bones.  It  is  fixed  by  its  base 
to  the  circumference  of  the  acetabulum,  beyond  the  cotyloid 
ligament,  and  to  this  ligament  itself,  where  the  latter  subtends 
the  notch.  It  embraces  that  part  of  the  head  of  the  os  femoris 
which  projects  above  the  margin  of  the  acelabulum,  and  de- 
scends along  the  neck  to  its  root.  It  is  longer  in  front;  is  fixed 
there  to  the  oblique  line  which  runs  between  the  two  trochan- 
ters,  and,  behind,  into  the  root  of  the  neck,  a  little  in  advance 
of  the  posterior  oblique  ridge,  and  in  such  a  manner  as  to  leave 
a  small  part  of  the  neck  of  the  os  femoris  bare  below  it.  Above, 
it  is  fixed  to  the  neck,  just  below  the  rough  fossa  in  the  tro- 
chanter  major;  and  on  the  under  surface  of  the  neck  it  adheres, 

*  Antonius  et  Caldani,  Tabula  II. 


ARTICULATIONS  OF  THE  LOWER  EXTREMITIES.  301 

just  above  the  trochanter  minor.  It  is  strengthened  in  several 
places  by  processes  from  the  fascia  lata  femoris,  which  descend 
to  it  between  the  muscles  surrounding  the  hip  joint.*  Its  thick- 
ness is  considerable,  but  variable.  In  front,  and  above,  it  is 
remarkably  strong,  is  two  or  three  lines  thick,  where  it  is  re- 
enforced  by  a  large  fasciculus  of  fibres  coming  from  the  ante- 
rior inferior  spinous  process  of  the  ilium,  and  descending,  lon- 
gitudinally, to  the  anterior  oblique  ridge  of  the  os  femoris. 
The  internal  and  posterior  portions  of  the  orbicular  or  capsular 
ligament  are  not  so  thick;  it  is,  indeed,  very  thin  near  the  pos- 
terior ridge  of  the  os  femoris,  not  more  than  half  a  line,  and 
has  a  number  of  holes  in  it  for  the  passage  of  vessels.  It  is 
strengthened,  internally,  by  some  fibres  coming  from  the  supe- 
rior margin  of  the  thyroid  foramen. 

This  capsular  ligament  keeps  the  bones  closely  applied  (o 
each  other,  and  is  by  no  means  so  loose  as  the  corresponding 
one  of  the  shoulder  joint.  Its  fibres  are  very  irregular,  gene- 
rally, in  their  course,  and  difficult  to  follow. 

The  strength  of  this  articulation  depends  principally  on  the 
muscles  which  surround  it,  of  which  the  rectus  femoris,  and 
the  iliacus  internus  and  psoas  magnus  united,  are  in  front;  be- 
tween the  latter  two  and  the  capsule,  is  a  bursa  mucosa. 
Within,  are  the  pectineus  and  the  obturator  externus;  behind, 
are  the  quad  rat  us,  the  gemini,  the  obturator  internus,  and  the 
pyramidalis;  above  and  behind,  are  the  glutei. 

The  Synovial  Membrane  is  a  complete  sac,  displayed  over 
the  articular  surfaces  of  the  bones,  and  the  internal  face  of  the 


*  Scemmerinor,   De  Corp.  Hum.  Fabrica,  vol.  ii.  p.  61,  1794.     Andrew   Fyfe, 
Compendium  of  Anat.  Philad.  1807,  vol.  i.  p.  179. 

For  an  interesting  account  of  the  connexion  of  this  capsule  witli  the  fascia  fe- 
moris, sec  Anatomical  Investigations,  by  J.  D.  Godman,  M.  D.,  Philad.  1824. 
The  author,  in  following  the  sheaths  of  the  muscles,  or,  in  other  words,  the  pro- 
cesses of  the  fascia  lata,  between  the  muscles,  to  the  capsule,  with  great  attention, 
has  been  brought  to  the  conclusion  that  tiro  capsule  is  formed  entirely  from  them, 
He  has  presented  the  same  views  in  regard  to  the  shoulder  joint,  and  others 
Though  not  disposed  to  concur  in  so  general  an  inference  on  the  source  of  cap- 
sular ligaments,  inasmuch  as  their  peculiar  texture  is  opposed  to  it,  and  many 
other  circumstances  in  their  anatomical  arrangement,  I  have  yet  to  express 
great  satisfaction  in  the  fidelity  with  which  these  connexions  of  the  larger  joints 
have  been  traced. 
VOL.  I.— 26 


302  SKELETON. 

capsule.  It  is  separated  from  the  roughness  at  the  bottom  of 
the  acetabulum,  by  the  existence  there  of  a  pad  of  very  vascu- 
lar, fine,  fatty  matter,  from  which,  according  to  Bichat,  it  may 
be  raised  by  blowing  beneath  the  ligament  of  the  notch,  at  the 
point  where  the  blood  vessels  enter.  Coming  from  the  aceta- 
bulum, it  covers  the  articular  face  of  the  cotyloid  ligament,  and 
is  then  reflected  to  the  capsule,  to  which  it  gives  a  polished  in- 
ternal face,  and  from  which  it  may  be  dissected.  On  reaching 
the  root  of  the  neck  of  the  os  femoris,  it  forms  small  duplica- 
tures,  and  is  reflected  upwards  along  the  neck  to  the  head, 
being  separated  from  the  neck  by  periosteum,  or  by  a  fibrous 
tissue,  which  M.  Boyer  considers  a  continuation  of  the  capsule. 
It  covers  all  the  head,  except  the  point  of  attachment  for  the 
round  ligament,  and  to  the  latter  it  gives  a  sheath,  which,  at 
the  other. end,  is  continuous  with  the  part  of  the  synovial  mem- 
brane covering  the  fatty  matter.  From  the  latter  circumstance, 
arises  a  deceptive  appearance  of  the  round  ligament  being  in- 
serted into  the  roughness  in  the  bottom  of  the  acetabulum.* 


Of  the  Knee  Joint. 

It  is  formed  by  the  os  femoris,  the  tibia,  and  the  patella,  the 
particular  modelling  of  whose  surfaces,  for  the  purpose,  has 
been  described.  These  surfaces  are  all  covered  by  a  uniform 
lamina  of  cartilage,  and  are  held  together  by  an  apparatus 
which  for  the  number  of  its  parts  and  their  arrangement,  makes 
this  the  most  composite  joint  in  the  skeleton. 

The  most  superficial  layer  of  the  knee  joint  is  the  fascia  lata 
of  the  lower  extremity,  which,  in  passing  down  from  the  thigh 
to  the  leg,  is  so  near  the  cavity  of  the  articulation  on  each  side 
of  the  tendon  of  the  patella,  that  it  is  by  Weilbrecht  spoken  of 
under  the  term  of  Common  Investment  (Involucrum  Generate.) 
It  is  here  not  only  a  continuation  of  the  fascia  femorig,  but  this 

*  I  have  found,  in  one  instance,  Dec.  10,  1838,  the  capsular  ligament  of  this 
joint  with  a  large  opening,  nine  by  eighteen  lines,  in  front,  and  the  synovial 
membrane  communicating  through  it  with  the  bursa  between  the  trcchlea  of  the 
ilium  and  the  iliacus  internus  muscle.  A  similar  arrangement  existed  on  both 
sides  of  the  body,  every  thing  else  being  normal.  Such  a  condition  must,  of 
course,  favour,  under  suitable  circumsiarsces,  the  internal  dislocation  of  the  oa 
emoris.  It  was  repeated  in  another  subject,  Jan.  2,  1830. 


ARTICULATIONS  OF  THE  LOWER  EXTREMITIES.  303 

fascia  is  increased  and  thickened  by  an  aponeurosis,  which 
springs  from  the  inferior  extremity  of  the  extensor  muscles  on 
the  thigh.  The  membrane  thus  formed  covers  both  the  patella 
and  its  ligament,  and  extends  on  each  side  to  the  lateral  liga- 
ments of  the  joint,  to  which  it  adheres;  it  may  be  traced  even 
behind  them,  but  there  it  becomes  indistinct,  loose,  and  blended 
with  common  cellular  and  adipose  membrane.  The  involu- 
crum  adheres  strongly  to  the  internal  and  external  condyle?, 
and  to  the  head  of  the  tibia;  it  has  oblique  fibres  on  the  patella, 
transverse  ones  on  the  ligament  of  the  latter,  and  longitudinal 
ones  on  each  side.  It  is  in  contact  with  ihe  synovial  mem- 
brane of  the  joint,  except  in  the  middle  portion,  where  it  is  se- 
parated from  it  by  the  patella,  and  its  tendon,  and  some  adi- 
pose matter.  It  may  be  dissected  without  difficulty  from  the 
subjacent  parts,  by  which  the  ligament  of  the  patella,  and  the 
synovial  membrane  are  brought  into  view. 

The  Ligament  of  the  Patella  being  situated  at  the  fore  part 
of  the  articulation,  though  separated  from  the  extensor  muscles 
by  the  intervention  of  the  patella,  is,  neverthless,  their  tendinous 
insertion  into  the  leg.  It  arises  from  the  whole  inferior  margin 
of  the  patella,  and  is  inserted  into  the  tubercle  of  the  tibia.  It 
consists  in  longitudinal,  closely  compacted  fibres,  of  a  character 
entirely  tendinous;  the  more  superficial  of  them  give  a  layer  to 
the  front  of  the  patella,  and  in  the  fracture  of  the  latter  some- 
times prevent  a  separation  of  its  fragments.  In  front,  as  just 
mentioned,  it  is  in  contact  with  the  involucrum  generale;  behind, 
is  a  large  mass  of  fat  placed  between  it  and  the  synovial  mem- 
brane of  the  joint;  and  on  the  same  surface,  but  lower  down,  it 
is  in  contact  with  a  bursa  mucosa  fixed  between  it  and  the  tri- 
angular flatness  of  the  tibia  above  the  tubercle'. 

A  posterior  ligament,  an  internal  and  an  external  lateral  liga- 
ment, two  crucial  ligaments,  two  semi-lunar  cartilages,  and  a 
synovial  membrane,  compose  the  remaining  apparatus  of  the 
joint. 

The  Posterior  Ligament  (Lig.  Posticum,}  is  a  fibrous  expan- 
sion on  the  back  of  the  knee  joint,  which  may  be  considered  as 
the  proper  capsular  ligament  at  this  point,  and  has  its  fibres  ex- 


304  SKELETON. 

tending  obliquely  from  the  external  condyle  of  the  os  femoris 
to  the  posterior  part  of  the  head  of  the  tibia.  It  is  frequently 
called  the  ligament  of  Winslo-w,  and  by  the  French  anatomists 
is  considered  as  one  of  the  divisions  of  the  tendinous  insertion  of 
the  scmUmernbranosus  muscle,  in  consequence  of  its  close  con- 
nexion with  it.  There  are  several  foramina  or  interstices  in  it, 
which  permit  a  passage  of  blood  vessels  to  the  fatty  matter 
placed  between  it  and  the  crucial  ligaments;  and  beneath  it 
there  are  some  transverse  fibres. 

The  Inlernal  Lateral  Ligament  (Lig.  Laterals  Internum)  is  a 
flattened  fasciculus  of  fibres  placed  at  the  internal  side  of  the 
joint.  It  arises  from  the  tuberosity  on  the  inner  side  of  the  in- 
ternal condyle,  and  descending  vertically  is  slightly  attached  to 
the  inner  semi-lunar  cartilage,  and  is  then  inserted  into  the  su- 
perior margin  and  the  internal  face  of  the  head  of  the  tibia  for 
two  inches  or  more,  increasing  in  breadth  as  it  descends.  On 
the  one  side  it  is  in  contact  with  the  synovial  membrane,  and  on 
the  other,  with  the  invohicrum  and  the  tendon  of  the  sartorius, 
the  scmi-lendinosus,  and  the  gracilis, 

The  External  Lateral  Ligament  (Lig.  Laterale  Extemum 
Longum,)  placed  on  the  external  side  of  the  joint,  is  nearer  its 
posterior  face  than  the  internal  ligament.  It  arises  from  the 
tuberosity  on  the  outer  face  of  the  external  condyle,  above  and 
behind  the  tendinous  origin  of  the  popliteus  muscle,  and  is  in- 
serted into  the  external  part  of  the  superior  extremity  of  the 
fibula,  being  covered  in  almost  its  whole  extent  by  the  tendon 
of  the  biceps.  Its  inner  face  is  in  contact  with  the  synovial 
membrane,  and  ihc  articular  vessels.  Its  rounded  form  and 
shining  appearance  make  it  look  very  much  like  a  tendon.  Be- 
hind it,  occasionally,  is  a  small  fasciculus,  called  by  some  the 
short  external  lateral  ligament,  which  passes  from  the  external 
condyle  to  the  head  of  the  tibia. 

The  Crucial  Ligaments  (Lig.  Cructata,)  two  in  number,  are 
named  from  their  crossing  one  another  laterally,  and  thereby 
forming  a  figure,  resembling  the  letter  X,  or  a  Malta  cross. 
They  arc  situated  at  the  posterior  part  of  the  articulation  be- 
tween the  posterior  ligament  and  the  synovial  membrane.  One 


ARTICULATIONS  OF  THE  LOWER  EXTREMITIES.  305 

of  them  is  called  anterior,  and  the  other  posterior,  from  their  re- 
lative situations  to  each  othcc.  The  first  arises  from  the  inter- 
nal face  of  the  external  eondyle,  by  a  depression  near  the  bot- 
tom of  the  notch  and  just  at  the  margin  of  the  articular  surface ; 
it  descends  forwards,  and  is  inserted  immediately  in  front  of 
the  little  ridge  between  the  articular  fac.es  of  the  tibia-.  The 
second  arises  from  the  bottom  of  the  notch  between  the  condyles, 
just  behind  the  trochlea  for  the  patella,  upon  a  surface  that  may 
be  considered  as  belonging  to  the  internal  eondyle;  it  descends 
backward-s  :md  is  inserted  into  the  rough  surface  behind  the 
aforesaid  spine  or  ridge  of  the  Libia.  The  crucial  ligaments  arc- 
large,  round,  and  composed  of  parallel  fibres  very  closely  com- 
pacted; their  strength  is  very  considerable,  and  they  servo  not 
only  to  limit  the  extension  of  the  leg,  but  also  to  cheek  any 
^  like  rotation  inwards. 

The  Semilunar  Cartilages  (Cartllagines  Scmilunares,  fal- 
are  two  in  number;  one  placed  on  either  side  of  the  su- 
perior face  of  the  tibia,  hoi  ween  it  and  the  condyles  of  the  os 
femoris.  Their  .shape  is  su.Ticiently  indicated  by  their  names, 
and  as  they  are  placed  on  the  circumference  of  each  articular 
surface  of  the  tibia,  leaving  the  middle  uncovered,  they  increase 
considerably  the  depth  of  the  concavities  for  receiving  the  con- 
dyles. Their  external  circumference  is  thick,  whereas,  the  in- 
ternal is  reduced  by  a  gradual  diminution  of  their  thickness,  to 
a  very  thin  edge.  The  internal  cartilage  is  but  little  more  than 
a  semicircle,  and  is  longer  in  its  antero-posterior  diameter  than 
in  its  transverse:  on  the  other  hand,  the  external  is  almost  cir- 
cular; an  arrangement  by  which  each  is  suited  to  its  rcspectirc 
surface.  They  adhere  by  their  greater  circumferences  to  the 
fibrous  matter  surrounding  the  joint,  particularly  the  lateral  li- 
gaments, but  not  so  closely  as  to  prevent  their  sliding  back- 
wards and  forwards  in  the  flexions  of  the  leg.  The  tendon  of 
the  popliteus  adheres  to  the  external,  either  directly  or  by  the 
intervention  of  a  small  synovial  sac. 

The  internal  semiluriar  cartilage  is  attached  by  its  fore  ex- 
tremity to  the  anterior  internal  side  o"!"  the  roughne  ;s  in  front  of 
the  ridge,  called  spinous  process,  on  the  top  of  the  tibia,  and  by 
the  hind  extremity  to  the  posterior  face  of  the  base  of  the  ridge, 
just  in  advance  of  the  posterior  crucial  ligament.  The  external 
cartilage  is  attache  1  by  its  anterior  end,  also,  to  the  roughru 

20* 


306  SKELETON. 

in  front  of  the  ridge;  but  this  attachment  is  considerably  behind 
the  corresponding  one  of  the  internal  cartilage,  and  is  somewhat 
blended  with  the  anterior  crucial  ligament:  the  posterior  end  is 
fixed  into  the  depression  on  the  summit  of  the  ridge  or  spinous 
process,  and  is  there  between  the  two  crucial  ligaments.  The 
anterior  extremities  of  the  two  cartilages  are  united  by  a  trans- 
verse ligamentous  fasciculus  a  line  in  thickness,  which  is  rather 
inconstant;  but  when  found,  is  in  front  of  the  anterior  crucial 
ligament.  These  bodies,  though  presenting  an  appearance  cor- 
responding with  cartilages,  on  their  surface,  are,  nevertheless, 
formed  principally  from  concentric  ligamentous  fibres;  the  cha- 
racter of  vyhich  is  very  evident  at  their  extremities,  and  when, 
they  are  lacerated. 

The  Synovial  Membrane  is  thin,  loose,  and  delicate,  and,  as 
in  other  joints,  is  a  perfect  bag,  covering  the  articular  faces  of 
the  bones,  and  reflected  from  the  one  to  the  other.  As  there  is 
>io  regular  capsular  ligament  to  the  knee  joint,  the  synovia! 
membrane  is  very  distinct  on  each  side  of  the  tendon  of  the  pa- 
tella; and  comes  in  contact  there  with  the  fascia  lata,  or  involu- 
crum,  as  it  passes  from  the  thigh  to  the  leg.  The  synovia!'  mem- 
brane, after  covering  the  articular  faces  of  the  tibia,  is  reflected 
from  their  margin  upon  the  semilunar  cartilages  so  as  to  invest 
their  inferior  and  superior  surfaces;  it  then  ascends  to  the  con- 
dyles  of  the  os  femoris.  It  covers  the  condyles,  laterally,  as 
well  as  on  their  articular  faces,  and  leaves  thereby  half  an  inch 
or  more  of  their  circumference  on  each  side  of  the  tro-chlea  of 
the  patella,  included  in  the  periphery  of  the  joint.  The  syno- 
vial  membrane,  anteriorly,  being  separated  from  the  tendon  of 
the  patella,  by  the  large  mass  of  fat,  then  covers  the  posterior 
face  o-f  the  patella,  and,  rising  up  still  farther,  lines  the  posterior 
face  of  the  tendons  of  the  extensor  muscles  for  the  distance  of 
three  inches  or  thereabouts.  The  superior  end  of  this  reflection 
is  formed  into  a  small  pouch,  communicating  freely  with  the 
general  cavity,  but  marked  off  from  it  by  a  partial  and  variable 
septum  on  each  side.  Some  anatomists  consider  the  pouch  as 
a  bursa,but  it  is  so  seldom  seen  entirely  distinct  from  the  joint, 
that  it  answers  better  to  describe  it  as  a  part  only  of  the  gene- 
ral reflection.  The  synovial  membrane,  at  the  sides  of  the  joint-,. 
i?  in  contact  wiih  the  lateral  ligaments.  Behind,  it  is  reflected 


ARTICULATIONS  OF  THE  LOWER  EXTREMITIES.  307 

on  the  anterior  surface  of  the  tendinous  origins  of  the  gastroc- 
nemius,  and  envelops  the  tendon  of  the  popliteus;  it  also  invests 
the  crucial  ligaments,  but  in  such  a  way  as  to  leave  them  out 
of  its  cavity. 

The  mass  of  fat  behind  the  tendon  of  the  patella  forms,  just 
below  the  latter,  a  ridge  on  each  side,  protruding  into  the  arti- 
culation, and  having  a  fringed  summit  formed  by  a  doubling  of 
the  synovial  membrane.  The  external  ridge  is  the  Ligamentum 
Alare  Minus  Externum,  and  the  other  the  Ligamentum  Alare 
Majus  Internum.  These  ridges  converge  at  their  lower  extre- 
mities, and  from  their  point  of  union  proceeds  a  duplicature  of 
the  synovial  membrane,  in  front  of  the  anterior  crucial  ligament; 
the  other  end  of  the  duplicature  is  attached  to  the  posterier  ex- 
tremity of  the  groove,  in  the  middle  of  the  trochlea,  for  the  pa- 
tella. This  duplicature  is  the  Mucous  Ligament,  (Ligamentum 
Mucosum.) 

Of  the  Peroneo-Tibial  Articulation. 

The  tibia  and  fibula  are  held  together  by  three  places  of 
union,  one  above,  another  below;  and,  thirdly,  the  ligament 
which  fills  up  the  space  between  the  bodies  of  the  bones. 

1.  The  Superior  Articulation,  formed  by  the  upper  extremity 
of  the  fibula  and  the  outer  side  of  the  head  of  the  tibia,  is  entire- 
ly disconnected  with  the  cavity  of  the  knee  joint,  and  has  no- 
thing in  common  with  its  apparatus,  except  the  external  lateral 
ligament,  which  has  been  described.  The  articular  faces  are 
small,  and  covered  with  cartilage;  an  anterior  and  a  posterior 
ligament,  and  a  synovial  membrane,  hold  the  bones  together  at 
this  point. 

The  anterior  ligament  is  attached  by  one  end  to  the  front  of 
the  head  of  the  fibula,  and  proceeding  upwards  and  inwards,  is 
inserted  by  the  other  into  the  contiguous  part  of  the  head  of 
the  tibia,  before  the  articular  facet.  The  fibres  are  separated 
into  fasciculi,  leaving  interstices  between  them  for  cellular  sub- 
stance. 

The  posterior  ligament  is  narrower  than  the  anterior,  but  its 
fibres  are  more  compact;  and,  like  the  anterior,  they  observe  a 
transverse  course,  being  attached  by  the  one  end  to  the  head  of 
the  fibula,  and,  by  the  other,  to  the  head  of  the  tibia.  The  pop- 


308  SKELETON. 

liteus  muscle  covers  them.  This  joint  is  also  strengthened  by 
other  ligamentous  fibres,  and  by  the  insertion  of  the  tendon  of 
the  biceps. 

The  synovial  membrane  is  reflected  over  the  articular  faces 
and  the  ligaments  described,  and  has  nothing  of  particular  inte- 
rest in  it.  Occasionally,  the  synovial  membrane  of  the  knee 
joint  runs  into  it. 

2.  The  Inferior  Articulation,  which  is  formed  between  the 
lower  extremities  of  the  bones,  is  not  incrusted  by  cartilage,  ex- 
cept to  the  breadth  of  a  line  at  its  lower  part,  bordering  on  the 
ankle  joint. 

Its  anterior  ligament  is  broad,  and  covers  the  face  of  the 
bones  which  are  in  apposition.  Attached  by  the  one  side  to 
the  front  of  the  lower  extremity  of  the  fibula,  its  fibres  pass  ob- 
liquely upwards  and  inwards,  to  be  inserted  into  the  correspond- 
ing part  of  the  tibia.  Several  interstices  exist  in  it  for  the  pas- 
sage of  vessels,  and  it  is  covered  by  the  peroneus  tertius.  Its 
lower  margin  is  in  contact  with  the  astragalus,  and  forms  a  por- 
tion of  the  ankle  joint. 

The  posterior  ligament,  in  the  arrangement  and  course  of  its 
fibres,  corresponds  with  the  anterior;  being  attached  by  one  side 
to  the  posterior  face  of  the  fibula,  and  by  the  other  to  the  cor- 
responding part  of  the  tibia.  Like  the  other,  its  fibres  are  longer 
near  the  ankle  joint  than  above.  Its  lower  margin  is  in  contact 
with  the  astragalus,  and  is  connected  with  other  ligaments 
coming  from  the  fibula. 

In  the  space  between  the  anterior  and  the  posterior  ligament, 
where  the  bones  touch,  they  are  agglutinated  by  a  short,  strong, 
fibrous  tissue,  leaving  intervals  occupied  by  adipose  matter.  It 
contributes  much  to  the  solidity  and  immobility  of  this  articula- 
tion. 

3.  The  Interosseous  Ligament  (Membrana  Inlerossea,)  is  ana- 
logous to  that  in  the  fore  arm,  by  being  a  membrnne  stretched 
between  the  two  bones.     It  arises  from  the  ridge  on  the  outer 
face  of  the  tibia,  and  is  attached  to  the  corresponding  ridge  on 
the  inner  face  of  the  fibula.     It  is  broader  above  than  below, 
being  at  the  latter  point  continuous  with  the  fibrous  structure 
\yhich  agglutinates  the  bones.     Just  below  the  head  of  the  fibula 


ARTICULATIONS  OF  THE  LOWER  EXTREMITIES.  309 

is  a  large  hole  for  transmitting  the  anterior  tibial  vessels,  and 
the  origin  of  the  tibialis  posticus  muscle.  It  also  presents,  in  its 
descent,  several  smaller  foramina  for  the  passage  of  vessels.  Its 
fibres  are  strong  and  unyielding,  and  run  obliquely  downwards 
from  the  tibia  to  the  fibula.  It  is  covered  in  its  whole  length, 
both  before  and  behind,  by  muscles,  and  serves  as  an  origin  to 
them  and  as  a  means  of  attachment  between  the  hones* 


Of  the  Ankle  Joint. 

The  articular  surfaces,  here,  being  covered  by  cartilage  as 
in  other  moveable  joints,  are  formed  by  the  astragalus  being 
received  into  a  deep  cavity  made  by  the  tibia  and  the  fibula. 
The  capsular  ligament,  properly  speaking,  does  not  exist  ei- 
ther on  the  front  or  the  back  of  the  joint,  and  is  represented, 
there,  by  a  few  scattered,  loose  fibres,  on  the  periphery  of  the 
synovial  membrane.  An  internal  and  an  external  lateral  liga- 
ment, with  the  synovial  membrane,  constitute  the  whole  appa- 
ratus. 

The  Internal  Lateral  Ligament,  also  called  the  Deltoid,  (Lig. 
Deltoideum)  arises  from  the  whole  inferior  margin  of  the  mal- 
leolus  internus,  and  with  particular  strength  from  the  depress- 
ion which  exists  in  it:  it  then  descends  and  is  inserted  into  the 
internal  face  of  the  astragalus,  and  into  the  lesser  apophysis  of 
the  os  calcis,  which  lies  just  below  it.  This  ligament  is  broad, 
thick,  quadrilateral,  and  composed  of  fibres  which  descend 
obliquely  backwards.  The  tendon  of  the  tibialis  posticus  runs 
in  a  trochlea  which  is  formed  on  the  internal  face  of  this  liga- 
ment. 

The  External  Lateral  Ligament  (Lig.  Triquelrum)  consists  in 
three  distinct  fasciculi,  of  which  one  is  anterior,  another  pos- 
terior, and  the  third  in  the  middle.  The  anterior  arises  from 
the  lower  extremity  of  the  malleolus  externus,  and,  running  in- 
wards and  forwards,  is  inserted  into  the  outer  face  of  the  as- 
tragalus in  front  of  the  surface  for  the  fibula.  The  posterior 
arises  from  the  depression  in  the  extremity  of  the  malleolus 
externus,  and,  running  inwards  and  backwards,  is  attached  to 
the  point  of  the  astragalus,  at  the  outside  of  the  groove,  for 


310  SKELETON. 

the  tendon  of  the  flexor  pollicis.  The  middle  arises  from  the* 
pointed  termination  of  the  malleolus  externus,  and,  descending 
beneath  the  tendons  of  the  peronei  muscles,  is  attached  to  the 
external  face  of  the  os  calcis,  below  the  surface  for  the  astra- 
galus. These  fasciculi  arc  composed  of  strong  longitudinal 
and  parallel  fibres.  The  posterior  is  lander  than  either  of  the 
others,  and  occasionally  detaches  a  part  which  is  inserted  into 
the  posterior  margin  of  the  articular  face  of  the  tibia. 

The  Synovial  Membrane  is  reflected,  as  usual,  over  the  arti- 
cular surfaces,  and  from  one  bone  to  the  other.  It  sends  up  a, 
short  process  of  a  line  in  length  between  the  tibia  and  the  fibula, 
it  is  remarkably  loose  in  front  and  behind,  and  has  on  its  super- 
ficial face  a  considerable  quantity  of  adipose  matter,  which  can- 
not be  easily  detached  from  it.  It  commonly  contains  an  un- 
usual quantity  of  synovia. 

Of  the  Articulations  of  the  Foot. 

Of  the  Tarsal  Articulations.—  }.  The  Os  Astragalus  is 
united  to  the  Os  Calcis  by  a  double  articular  surface,  which  has 
been  described.  The  ligaments  which  hold  them  together  are 
as  follow: — 

The  Interosseous  Ligament  is  pla-ced  between  the  two  bones, 
so  as  te  occupy  the  large  oblique  fossa  between  the  double  ar- 
ticular surface  in  each.  It  is  a  collection  of  very  strong,  short 
fibres,  with  interstices  for  fatty  matter,  which,  arising  from  the 
whole  length  of  the  groove  in  the  astragalus,  descends  to  be  in- 
serted into  corresponding  points  in  the  groove  of  the  os  calcis. 
Where  the  fossa  is  narrow,  as  it  is  behind,  the  ligament  is  thin 
and  flat,  but  it  augments  considerably  in  front,  where  there  is 

more  room  for  it. 

• 

•  The  posterior  Ligament  arises  from  the  posterior  margin  of 
the  astragalus,  and,  descending  obliquely  inwards,  is  inserted 
into  the  adjacent  portion.of  the  os  calcis.  Its  fibres,  are  blend- 
ed with  those  of  the  Deltoid  Ligament,  and  on  their  posterior 
face  they  form  a  ligamentous  trochlea  for  the  tendon  of  the 
flexor  pollicis. 


ARTICULATIONS  OF  THE  LOWER  EXTREMITIES.  311 

This  articulation  is  also  strengthened  by  the  insertion  of  the 
lateral  ligaments  of  the  ankle  joint  into  the  os  calcis. 

The  Synovial  Membrane  forms  a  distinct  cavity  on  the  pos- 
terior and  larger  articular  face  of  the  two  bones,  and  is  in  con- 
tact with  the  fatty  matter  in  advance  of  the  tendo-achillis. 

2.  The  Articulation  of  the  Astragalus  with  the  scaphoides  is 
formed  by  the  convex  head  on  the  part  of  the  former,  and  by 
the  concavity  on  the  part  of  the  latter.  It  is  covered,  above,  by 
a  thin,  broad  ligament,  with  parallel  and  oblique  fibres,  which, 
arising  from  the  superior  and  internal  face  of  the  astragalus,  are 
implanted  into  the  upper  face  of  the  scaphoides,  some  of  its 
fibres  extending  over  to  the  cuneiform  bones.  It  is  covered, 
above,  by  the  tendons  of  the  extensor  muscles  of  the  toes  and 
of  the  tibialis  anticus. 

On  the  under  surface  of  the  foot,  this  articulation  is  support- 
ed by  two  ligaments,  called  the  Calcaneo  Scaphoid,  (Lig.  Pla- 
num,)  from  their  origin  and  insertion.  The  interior  one  arises 
from  the  internal  margin  of  the  lesser  apophysis  of  the  os  cal- 
cis, and,  running  obliquely  forwards  and  inwards,  is  inserted 
into  the  under  and  internal  surface  of  the  os  scaphoides.  It  is 
a  very  thick,  flattened  fasciculus,  on  the  under  surface  of  which 
is  formed  the  ligamentous  trochleee,  in  which  run  the  tendons 
of  the  flexor  pollicis  and  flexor  longus  digitorum,  and  which 
surface  is  also  in  contact  with  the  tendon  of  the  tibialis  posti- 
cus.  By  subtending  the  head  of  the  astragalus,  it  contributes 
largely  to  the  keeping  of  it  in  its  place  in  the  erect  position. 
The  External  Calcaneo  Scaphoid  Ligament,  placed  at  the  outer 
margin  of  the  last,  arises  from  the  under  surface  of  the  greater 
apophysis  of  the  os  calcis,  and  running  obliquely  inwards  arid 
forwards,  is  implanted  into  the  under  external  surface  of  the 
scaphoides.  It  consists  in  two  or  more  short,  strong  fasciculi. 

The  Synovial  Membrane  of  the  articulation  between  the  as- 
tragalus and  the  scaphoides  covers  the  articular  faces  of  these 
bones,  and  lines  the  ligaments  above  and  below.  A  reflection 
of  it,  also,  lines  the  articulation  between  the  os  calcis  and  the 


312  SKELETON. 

astragalus,  in  front  of  the  rough  fossa  which  is  occupied  by  their 
interosseous  ligament. 

S.  The  Calcaneo  Cuboid  articulation,  formed  by  the  two 
bones  indicated  in  the  name,  is  maintained  by  two  ligaments, 
one  above,  the  other  below,  and  by  a  synovial  membrane. 

The  Superior  Calcaneo  Cuboid  Ligament  arises  from  the  up- 
per anterior  surface  of  the  os  calcis,  and  is  inserted  into  the 
adjoining  upper  surface  of  the  cuboides.  It  is  broad,  thin,  and 
quadrilateral,  with  short  parallel  fibres,  and  is  in  contact,  above, 
with  the  peroneus  tertius  tendon. 

The  Inferior  Calcaneo  Cuboid  Ligament,  (Lig.  Plantare,) 
placed  on  the  plantar  surface  of  the  foot,  is  remarkable  for  its 
size  and  extent.  It  consists  of  two  horizontal  planes  of  fibres, 
of  which  the  superficial  is  the  longest.  The  latter  arises  from 
the  back  under  surface  of  the  os  calcis,  and,  advancing  for- 
wards, its  fibres  are  inserted  into  the  summit  of  the  ridge  which 
traverses  the  cuboides  obliquely;  the  greater  part  of  them,  how- 
ever, go  beyond  this  point,  and,  dividing  into  fasciculi,  are  in- 
serted into  the  base  of  the  fourth  and  fifth  metatarsal  bones. 
The  tendon  of  the  peroneus  longus  is  confined  between  these 
fasciculi  and  the  under  surface  of  the  cuboides.  The  other 
plane  of  this  ligament  being  more  deeply  seated,  is  also  shorter. 
It  arises  from  the  front  under  surface  of  the  os  calcis,  where 
the  tuberosity  exists  at  this  point,  and,  by  advancing,  is  inserted 
entirely  into  the  oblique  ridge  of  the  euboides. 

The  Synovial  Membrane  being  reflected  over  the  articular 
surfaces  of  the  bones,  and  lining  the  ligaments,  is  uncovered  at 
several  places  above,  where  interstices  exist  between  the  fibres 
of  the  superior  ligament,  and  externally  it  is  contiguous  to  the 
tendon  of  the  peroneus  longus. 

4.  The  Scaphoid  and  the  Cuboid  bones  touch  at  the  external 
posterior  angle  of  the  cuneiforme  externum,  and  form,  there, 
occasionally,  a  distinct  articular  surface,  with  a  synovial  mem- 
brane. Besides  this  mode  of  union,  an  interosseous  ligament 


ARTICULATIONS  OF  THE  LOWER  EXTREMITIES.  313 

is  introduced  between  them.  On  the  dorsum  of  the  foot  there 
is  a  transverse  ligament  running  from  one  bone  to  the  other  be- 
neath the  extensor  tendons ;  and  on  the  sole  of  the  foot  there 
is  an  oblique  ligament,  which,  arising  from  the  under  surface  of 
the  scaphoides,  is  inserted  into  the  anterior  internal  margin  of 
the  cuboides. 

The  articular  surfaces  of  the  Cuboides  and  Cuneiforme  Ex- 
ternum,  which  are  in  contact,  besides  a  distinct  synovial  mem- 
brane, are  secured  by  transverse  and  oblique  ligamentous  fibres 
going  from  the  one  bone  to  the  other. 

5.  The  Articulation  between  the  scaphoides  and  the  three 
cuneiform  bones  is  secured  by  a  dorsal  and  a  plantar  ligament. 
The  dorsal,  arising  from  the  back  of  the  scaphoides,  is  divided 
into  three  fasciculi,  that  go,  respectively,  to  the  back  of  each 
cuneiform  bone;  of  these,  the  internal  is  the  strongest,  and  is 
particularly  well  marked  on  the  internal  face  of  the  cuneiforme 
internum.  The  plantar  ligaments  are,  also,  three  in  number, 
and,  having  a  sort  of  common  base  from  the  under  surface  of 
the  scaphoides,  by  being  divided  into  three  fasciculi,  as  the 
above,  are  inserted  into  each  cuneiform  bone.  They  are  not 
so  well  marked  as  the  upper  ones. 

The  cuneiform  bones  are  also  connected  together  above  and 
below,  by  short  transverse  ligaments  going  from  one  bone  to 
the  other,  and  holding  their  lateral  surfaces  in  contact.  Those 
below  are  not  so  distinct  as  the  upper  ones,  arid  are  blended 
with  the  insertions  of  the  tibialis  posticus. 

One  synovial  membrane  covers  the  articular  surfaces  of  the 
scaphoides  and  of  the  cuneiform  bones  which  are  in  contact; 
and  it  extends  itself  by  digital  processes  between  the  first  and 
second,  and  the  second  and  third  cuneiforms,  so  as  to  line  also 
the  articulations  there.  The  process  between  the  two  latter  is 
much  shorter  than  the  process  between  the  other  two,  which 
extends  itself  into  the  tarso-metatarsal  articulations,  after  the 
same  principle  which  is  observable  in  the  hand. 

VOL.  I.— 27 


314  SKELETON. 


Of  the  Tarso-Metatarsal  Articulations. 

The  articular  faces  of  the  bones,  here,  having  been  sufficient- 
ly described,  it  is  to  be  noted  in  addition,  that  besides  being 
covered  with  cartilage,  they  have  the  apparatus  of  the  movea- 
ble  articulations  generally,  in  ligaments  which  hold  them  toge- 
ther, and  in  synovial  membranes.  The  ligaments  are  above 
and  below. 

1.  The  articulation  of  the  first  metatarsal  bone  with  the  cu- 
neiforme  internum  is  one-third  of  an  inch  in  advance  of  the 
next,  and  completely  insulated  by  its  synovial  membrane:  it  is 
strongly  secured  by  ligamentous  fibres  above,  internally  and 
below,  which  give  it  almost  a  complete  capsule. 

2.  The  dorsal  or  upper  ligaments  of  the  remaining  metatar- 
sal bones  are  arranged  as  follow.     There  are  three  for  the  se- 
cond metatarsal;  one  comes  from  the  second  cuneiform,  one 
from  the  first,  and  another  from  the  third:  the  two  latter  are 
oblique;  and  they  all  converge  to  be  inserted  into  the  base  of 
the  bone  to  which  they  belong.     One  dorsal  ligament  passes 
from  the  third  cuneiform  to  the  base  of  the  third  metatarsal; 
it  is  sometimes  assisted  by  a  fasciculus  from  the  cuboides. 
From  the  superior  face  of  the  cuboid  bone  a  fasciculus  is  sent 
to  the  base  of  the  third  and  fourth  metatarsals. 

The  plantar  or  under  ligaments  are  arranged  on  the  same 
plan  with  the  dorsal.  Not  being  quite  so  strong,  they  are  re- 
enforced  by  the  fibrous  sheaths  of  the  flexor  tendons  which  lie 
upon  them. 

The  synovial  membrane,  which  is  reflected  over  the  articu- 
lar surfaces  between  the  second  and  third  metatarsals  and  their 
corresponding  cuneiforms,  is  the  elongation  of  the  digital  pro- 
cess sent  from  the  scaphoid  articulation  between  the  first  and 
second  cuneiforms.  This  process,  besides  extending  to  the 
aforesaid  tarso-metatarsal  articulations,  insinuates  itself  to  the 
articular  surfaces  on  the  sides  of  the  second  metatarsal  bone; 


ARTICULATIONS  OF  THE  LOWER  EXTREMITIES.  315 

but  a  distinct  synovial  capsule  is  sometimes  formed  between 
the  base  of  the  third  and  fourth  metatarsals. 

One  synovial  membrane  is  reflected  over  the  surfaces,  be- 
tween the  cuboides  and  the  last  two  metatarsals,  and  sends  in 
a  process  between  the  latter.  In  all  these  cases  the  synovial 
membranes  line  the  dorsal  and  plantar  ligaments  of  their  re- 
spective articulations. 

Of  the  Metatarsal  Articulations. 

The  metatarsal  bones,  with  the  exception  of  the  first,  articu- 
late with  each  other  by  the  contiguous  faces  of  their  roots; 
which  has  just  been  stated,  along  with  the  manner  of  their  get- 
ting at  these  points,  a  lining  of  synovial  membrane.  They  are 
farther  fastened  to  each  other  by  short  transverse  ligamentous 
fasciculi,  which  pass  from  the  base  of  one  to  the  base  of  the 
adjoining.  These  fasciculi  exist  both  on  the  upper  and  under 
surface  of  the  bones,  and  are,  therefore,  denominated  dorsal 
and  plantar  metatarsal  ligaments.  There  is  also  a  description 
of  interosseous  ligament  between  the  bases  of  these  bones,  oc- 
cupying the  space  intermediate  to  the  dorsal  and  plantar  liga- 
ments of  each. 

The  anterior  extremities  of  the  metatarsal  bones  are  not  in 
contact;  they  are,  however,  fastened  to  each  other  by  a  trans- 
verse or  Anterior  Plantar  ligament  on  their  under  surface,  the 
fibres  of  which  are  somewhat  blended  with  the  capsular  liga- 
ments of  the  first  joints  of  the  toes. 

Of  the  First  Joint  of  the  Toes. 

The  surfaces  of  the  bones  here  being  covered  with  cartilage, 
are  formed  into  an  arthrodial  articulation.  There  is  a  fibrous 
capsule  surrounding  the  articular  faces,  and  enclosing  the  sy- 
novial membrane.  This  capsule  is  considerably  thickened  be- 
low, where  the  flexor  tendons  pass  over  it ;  above,  it  does  not 
exist,  as  the  extensor  tendon  is  there  lined  by  the  synovial 
membrane:  on  each  side  it  is  also  thickened,  so  as  to  form  a 
lateral  ligament.  In  the  under  part  of  the  capsule  of  the  great 
toe,  we  find  on  each  side  the  sesamoid  bone.  These  joints  re- 


316  SKELETON. 

semble  so  strongly  the  corresponding  joints  of  the  fingers,  that 
a  farther  description  is  unnecessary. 

Of  the  Second  and  Third  Joints  of  the  Toes. 

From  the  shape  of  the  surfaces  of  the  bones  composing  them, 
these  are  simply  ginglymous  articulations.  They  have  their 
cartilaginous  incrustations,  synovial  membrane,  and  capsular 
ligament.  The  under  part  of  the  latter  is  much  thickened,  and 
forms  a  trochlea  for  the  flexor  tendons;  on  each  side  it  is  ar- 
ranged into  a  lateral  ligament,  and  above  it  is  defective,  as  the 
synovial  membrane  is  in  contact  with  the  extensor  tendon. 
These  joints  also  resemble  so  strongly  the  corresponding  ones 
of  the  fingers,  that  farther  description  is  unnecessary. 


BOOK    II. 


Of  the  Integuments  of  the  Body. 

THE  integuments  of  the  body  consist  in  the  Cellular  and 
Adipose  Substance,  and  in  the  Dermoid  Covering. 


PART    I. 

Cellular  and  Adipose  Substance. 

CHAPTER  I. 

OF  THE  CELLULAR  SUBSTANCE. 

THE  Cellular  Substance  (Textus  Cellulosus,  Mucosus)  is  an 
elementary  tissue,  and  is  more  generally  diffused  than  any  other 
of  the  body,  for  it  seems  to  be  quite  as  indispensable  to  the  lat- 
ter as  the  corpus  mucosum  is  to  vegetables.  It  is  found  abun- 
dantly beneath  the  skin;  between  muscles;  in  the  interstices  of 
muscles  and  of  other  parts ;  connecting  membranes  to  one  ano- 
ther; surrounding  organs;  entering  into  their  composition; 
gluing  them  together;  in  fine,  under  every  variety  of  circum- 
stance and  locality  of  which  the  human  organization  admits. 
Indispensable  as  it  is  to  the  texture  of  all  other  parts,  we  find 
it,  as  may  be  expected,  preceding  them  in  the  development  of 
the  foetus;  at  which  period  it  is  in  the  condition  of  a  fluid  slight- 
ly coagulated. 

When  examined  with  a  microscope,  as  it  winds  around  a 
muscle  and  introduces  itself  between  the  fasciculi  of  its  fibres, 
it  will  be  seen  that,  however  fine  the  latter  may  be,  yet  this  body 

27* 


318  INTEGUMENTS. 

is  interposed  between  them  in  thin  laminse.  On  separating 
these  fibres,  the  intervening  laminae  are  resolved  or  drawn  out 
into  fine  filaments,  which,  finally,  break  after  being  stretched  to 
a  certain  extent.  The  lamina  which  surrounds  the  whole  body 
of  the  muscle,  and  constitutes  its  sheath,  on  being  put  upon  the 
stretch,  also  tears  after  having  been  attenuated  into  still  thinner 
laminae  and  into  fibres. 

If  air  be  blown  into  the  sheath  of  a  muscle,  this  sheath  is 
distended  into  a  multitude  of  cells  of  various  forms  and  sizes, 
which  have  no  determined  shape,  and  do  not  upon  expulsion 
of  the  air  return  to  the  same  shape  upon  a  repetition  of  the  in- 
flation. These  cells  communicate  very  freely;  all  limpid  fluids 
pass  with  the  greatest  ease  from  one  to  the  other,  so  that  from 
any  single  point  they  may,  by  the  force  of  injection,  be  distri- 
buted throughout  the  body;  this  is  manifested  in  emphysema, 
where  from  a  small  wound  in  the  thorax,  air  becomes  univer- 
sally diffused.  Fluids  of  any  kind,  except  they  be  inspissated, 
when  deposited  in  these  cells,  are  subject  to  the  common  laws 
of  gravity,  and  continue  to  descend  successively  from  the  high- 
er to  the  lower  cells,  as  in  anasarca.  Blood  traverses  them 
very  readily  in  ecchymosis. 

Cellular  tissue  enjoys  a  good  deal  of  elasticity,  for  when 
stretched  it  readily  returns  upon  itself.  When  .very  thin,  as 
between  the  fibrillse  of  muscles,  it  is  colourless  or  nearly  so,  and 
of  a  gelatinous  or  glue-like  consistence ;  but  when  its  lamina? 
are  thicker,  it  is  of  an  opaque  white,  and  has  a  strength 
amounting  almost,  to  that  of  ligamentous  matter.  When  dried 
it  becomes  crisp  and  of  a  dark  brown ;  but  may  be  restored  to 
its  colour  and  condition  by  soaking  in  water.  It  is  only 
very  slightly  affected  by  the  usual  heat  of  the  culinary  pro- 
cesses of  roasting  or  boiling,  as  our  dishes  of  meat  daily  prove; 
but  may  be  resolved  into  gelatine  after  a  protracted  ebullition. 
Its  putrefaction  is  slow,  and  cannot  be  accomplished,  by  mace- 
ration, under  several  months. 

The  cellular  substance  is  pervaded  by  a  large  number  of 
blood  vessels,  the  majority  of  which  do  not,  in  a  natural  state, 
convey  obviously  red  blood;  but  if  any  portion  of  it  be  ex- 
posed for  a  short  time  to  the  air,  or  to  any  other  unusual  sti- 
mulus, it  quickly  becomes  suffused  with  red  blood,  circulating 
through  an  infinitude  of  channels.  It  cannot,  however,  be  con- 


CELLULAR  SUBSTANCE.  319 

ceded,  as  Ruysch  supposes,  that  it  is  formed  exclusively  of 
blood  vessels.  Some  anatomists,  indeed,  as  Haller  and  Pro- 
chaska,  allow  that  though  blood  vessels  ramify  through  it,  yet 
they  are  not  spent  upon  it,  or  do  not  form  a  part  of  its  organi- 
zation. The  distinction  is  rather  to  subtle,  to  be  readily  ad- 
mitted, and  seems,  moreover,  to  be  refuted  by  the  continued 
exhalation  and  absorption  which  is  going  on  within.  It  does 
not  appear  that  nerves  are  spent  upon  the  cellular  substance, 
though  they  pass  abundantly  through  it  to  their  respective 
organs. 

It  is  probable  that  the  granulations  on  which  injured  parts  of 
the  body  depend  for  their  restoration,  arise  from  this  cellular 
substance.  The  late  Professor  Wistar  attended  a  patient  for 
compound  fracture  of  the  leg,  with  a  large  wound,  which  was 
subsequently  covered  with  luxuriant  granulations.  The  limb 
was  suddenly  attacked  with  an  oedematous  swelling,  which  ex- 
tended itself  to  the  sore,  and  caused  its  granulations  to  tumefy, 
so  that  they  pitted  upon  pressure  precisely  like  other  parts.* 

The  most  generally  received  opinion  of  anatomists,!  in  re- 
gard to  the  arrangement  of  cellular  tissue  is,  that  it  results  from 
the  assemblage  of  a  multitude  of  lamella,  and  of  fine  soft  fila- 
ments, which,  being  variously  interwoven,  produce  a  series  of 
cells  all  communicating  one  with  another,  but  varying  in  their 
shape  and  size;  so  that  the  whole  cellular  substance  may  be 
considered  to  represent  a  single  cavity  subdivided  into  an  infini- 
tude of  smaller  ones.  To  this  it  is  objected, f  that  when  this 
tissue  is  accurately  examined,  it  appears  rather  as  a  homoge- 
neous, viscid,  and  only  partially  solidified  substance;  particular- 
ly in  the  inferior  orders  of  animals,  and  in  the  embryo  state  of 
the  more  exalted,  where  it  has  still  to  admit  the  deposite  or  for- 
mation of  the  several  organs.  That  the  same  is  manifested  at 
any  period  of  life;  for  neither  with  the  naked  or  assisted  eye 
does  it  assume  any  other  appearance.  That  its  laminated  and 
fibrous  condition,  when  such  does  appear,  is  owing  to  its  gluti- 
nous or  glue-like  consistence,  which  causes  it  to  assume  a  fac- 

*  System  of  Anat.  vol.  i.  p.  388,  2d  edition. 
t  Haller,  Beclard,  JBichat,  Wm.  Hunter,  &c. 

t  Bordeu,  Recherches  sur  le  Tissu  Muqueux  et  Celluleux.  Paris,  1790.  J. 
F,  Meckel,  Manuel  D'Anat.  vol.  i.  p.  105. 


320  INTEGUMENTS. 

titious  arrangement  upon  being  drawn  or  inflated.  For  ex- 
ample, if  one  separates  two  muscles  for  a  short  distance,  the 
cellular  substance  between  them  becomes  unequal  and  furrowed 
without  losing  its  cohesion;  but  if  they  be  farther  separated, 
filaments  and  cylindrical  columns  are  produced.  If  the  trac- 
tion be  then  suspended,  and  the  muscles  replaced,  the  filaments 
shorten,  and  are  finally  united  into  a  consistent  mass  whose 
parts  all  adhere  together.* 

While  such  tractions  are  going  on,  it  most  frequently  hap- 
pens that  air  is  insinuated  into  the  cellular  substance,  from  which 
corrres  the  appearance  of  small  cells  and  vesicles :  upon  the  es- 
cape of  this  air,  the  primitive  state  of  cohesion  is  restored,  and 
upon  a  renewal  of  the  traction,  cells  of  a  different  shape,  size, 
and  appearance  arise.  Again,  if  air  be  so  introduced,  one  may 
push  it  in  any  direction,  separate  its  globules,  collect  them  again, 
and  into  larger  masses;  vary  their  shape,  and,  in  fine,  by  such 
means  mould  the  supposed  cells  into  an  infinity  of  forms.  From 
these  considerations,  the  inference  is  plain,  that  when  cellular 
substance  is  drawn  it  must  yield  itself  into  filaments;  when  in- 
flated, as  the  air  acts  in  every  direction,  its  supposed  lamellae 
must  be  separated  and  assume  a  cellular  shape;  and,  by  the  ap- 
plication of  both  forces  at  once,  it  may  be  caused  to  assume 
both  a  cellular  and  a  filamentous  appearance.  Upon  the  whole, 
Meckel  conceives  that  the  term  Mucous  Tissue,  adopted  by 
Bordeu,  is  much  more  exact  than  the  one  of  Cellular  Tissue, 
now  most  generally  used. 

Notwithstanding  the  perfect  continuity  of  the  mucous  or  cel- 
lular substance  throughout  the  body,  anatomists  for  the  ease  of 
description  have  divided  it  into  External  and  Internal. 

The  External  Cellular  Substance  (Textus  Cellulosus  Inter- 
mediuSj  sen  laxus)  has  the  general  extent  and  shape  of  the  body 
and  of  its  organs,  so  that  if  it  were  possible  to  extricate  the  lat- 
ter from  their  envelope,  it  would  present  a  chamber  for  the 
lodgement  of  each  part.  But  the  walls  of  these  chambers 
would  not  all  be  of  the  same  thickness,  as  the  quantity  of  cel- 
lular substance  varies.  In  the  cranium  and  spinal  cavity  there 
is  very  little  of  it:  on  the  surface  of  the  head  and  in  the  orbits 
more:  about  the  trunk,  both  internally  and  externally,  it  is  abun- 
dant; in  the  extremities  still  more  so,  where  it  penetrates  between 
*  J.  F.  Meckel,  loc.  cit. 


CELLULAR  SUBSTANCE.  321 

the  muscles.  In  the  arm  pit,  in  the  groin,  and  in  the  neck,  all 
parts  where  much  motion  is  enjoyed,  it  is  unusually  abundant. 
The  foramina  of  the  cranium  and  of  the  spine,  establish  the 
points  of  connexion  of  the  cellular  substance  of  these  parts  with 
others  adjacent.  The  cellular  substance  of  the  face  is  conti- 
nued into  that  of  the  neck;  that  of  the  latter  is  continued  through 
the  upper  opening  of  the  thorax  upon  the  viscera  of  this  cavity; 
and  thence  through  the  openings  of  the  diaphragm,  along  the 
great  vessels  and  oesophagus  upon  the  viscera  of  the  abdomen 
and  pelvis.  The  cellular  substance  of  these  cavities  is  again 
continuous  with  the  deep-seated  cellular  substance  of  the  limbs 
at  the  arm  pit  and  at  the  groin.  The  trunk  of  the  body  being 
enveloped  by  one  broad  sheet  of  cellular  substance,  it  is  con- 
tinued superficially  to  the  limbs.* 

With  this  general  sketch  of  the  distribution  and  extent  of 
cellular  substance,  it  is  not  surprising  that  in  certain  bad  cases 
of  emphysema,  the  air  shows  itself  every  where,  even  at  points 
the  most  remote  from  the  lungs,  and  apparently  the  least  ex- 
posed to  the  accident,  as  the  interstices  of  muscles,  of  glandular 
organs,  and  so  on.  It  will  also  now  be  understood  how  this 
varied  distribution  of  cellular  substance  and  its  proteiform 
shape,  have  been  the  inexhaustible  but  delusive  source  of  ana- 
tomical discoveries  and  supposed  novelties,  under  the  name  of 
fascise,  sheaths  of  vessels,  and  so  on;  and  will  continue  to  be 
so,  to  such  as  do  not  recollect  that  all  these  things  are  included 
under  the  general  character  of  this  tissue;  and  that  each  mus- 
cle, each  viscus,  each  nerve,  and  each  blood  vessel,  has  its  own 
particular  chamber  under  this  multiform  arrangement,  which 
chamber  may  be  traced  to  or  from  any  other  point,  according 
to  fancy.  At  the  same  time  it  should  be  noted  that  many  of 
the  laminae  have  a  condensed  form,  which  renders  a  special 
knowledge  of  them  of  the  greatest  use  to  the  surgeon,  and 
which  is  elsewhere  succinctly  pointed  out,  with  the  description 
of  their  respective  organs. 

*  For  a  detailed  account  of  the  inflections  of  the  cellular  substance,  the  stu- 
dent may  consult  with  advantage,  Bordeu,  loc.  cit.  These  inflections  are  the  fas- 
ciae  of  modern  Surgical  Anatomy. 

Bichat,  Anatomic  Generate;  Systdme  Cellulare.     Paris,  1818. 

Andreas  Bonn,  de  Conlinuationibus  Membranarum,  in  Sandifort's  Thesaurus 
Dissertationum,  Rotterdam,  1769. 

Haller,  Element.  Physiol.  vol.  i.  1757. 


322  INTEGUMENTS. 

Anatomists  who  lived  at  a  period  much  less  illuminated  than 
the  present  on  the  subject  of  the  elementary  tissues  of  the  body, 
seem  to  have  seized  upon  the  idea  of  the  universal  inflection  of 
cellular  substance  over  the  surfaces,  and  through  the  texture 
of  the  several  organs.  Mangetus,*  without  pretending  to  ori- 
ginality, but  in  alluding  freely  to  the  observations  of  others, 
says,  "  Membrana  adiposa,  est  expansio  cellulosa,  quae  totum 
corporis  habitum,  paucissimis,  iisque  minimis  partibus  exceptis, 
circumambit;  etin  qua  materia  albicans  unctuosa,  sensu  expers, 
ad  partes  fovendas  ac  lubricandas  colligitur. — Hsec  membrana 
cellulosa  seu  pinguedinosa,  non  tantum  in  exterioribus  corporis 
reperitur;  sed  interius  in  intestinis,  mesenterio,  aliisque  prope 
omnibus  partibus,  non  exceptis  etiam  vasis  sanguiferis,  ut  suo 
loco  videbirnus,  observatur."  And  in  describing  the  aponeuro- 
tic  covering  of  the  body  and  of  the  limbs,  which  in  his  day 
was  called  Membrana  Musculosa,  from  some  false  notions  of 
its  nature,  he  adds,  "  Dicitur  oriri  a  dorsi  vertebris,  quia  scili- 
cet earum  spinis  firmiter  adhaeret,  inibique  multo  quam  alibi 
usquam  robustior  conspicilur.  Usus  est,  musculos  universim 
in  sua  sede  firmare,  iisque  quasi  thecam  praestare,  in  qua  ut 
supra  innuimus  laxius  sibi  cohaerente,  lubrice  moveri  queant." 
The  cellular  investments  of  the  muscles  the  same  author  calls 
Membrana  Musculi  Propria,  and  he  speaks  of  their  penetrating 
between  the  fasciculi  of  muscles,  and  most  evidently  those  of 
the  glutaeus  maximus  and  deltoides. 

The  Internal  Cellular  Membrane  (Textus  Cellularis  Stipatus) 
presents  itself  under  different  arrangements  according  to  the 
organ  or  part  whose  interstices  it  penetrates.  As  it  forms  in 
the  muscles  an  envelope  for  each  fasciculus  and  fibre,  if  the 
latter  by  any  art  could  be  withdrawn,  it  would  represent  a 
congeries  of  fine  parallel  tubes.  In  the  case  of  glandular  bo- 
dies the  internal  cellular  membrane  imitates  the  shape  of  their 
lobe-s,  lobules,  and  acini  or  small  graniform  masses,  and  may, 
therefore,  be  compared  to  a  sponge.  In  the  hollow  viscera,  as 
the  stomach  and  bladder,  it  unites  their  successive  laminae  to 
one  another.  In  the  .ligaments,  even  where  the  fibrous  struc- 
ture is  perfectly  evolved,  the  fibres  are  united  by  cellular  tissue 

*  Theatrum  Anatomicum,  Geneva,  1716,  vol.  i.  Ch.  Hi. 


CELLULAR  SUBSTANCE.  323 

in  their  interstices.  This  tissue  is  not  sufficiently  abundant  in 
the  bones,  tendons,  or  cartilages,  to  be  very  distinct;  but  from 
what  is  seen  of  it  in  the  forming  stage  of  the  embryo,  it  is  ne- 
vertheless ascertained  to  be  the  base  of  every  part.  In  glan- 
dular textures  it  is  frequently  spoken  of  under  the  name  of  pa- 
renchyma, 

Most  of  the  membranous  textures  of  the  body  may  by  ma- 
ceration be  resolved  into  this  mucous  or  cellular  tissue,  so  that 
we  hear  anatomists,  without  hesitation,  asserting,  that  under 
various  degrees  of  consistence,  it  forms  the  skin,  the  serous 
membranes,  the  vessels,  the  ligaments,  in  short,  almost  every 
thing  excepting  the  bones,  the  muscles,  the  nervous  system, 
and  the  glands,  and  they  only  depart  from  it  in  having  their 
globules  deposited  in  its  interstices.*  Meckel  even  adds  to  the 
list  the  epidermis. 

The  term  mucous  tissue  was  substituted  for  that  of  cellular, 
by  Bordeu,t  owing  to  its  glue-like  consistence,  and  to  its  re- 
semblance to  the  corpus  mucosum  of  vegetables.  Notwith- 
standing its  propriety  on  these  grounds,  yet  as  the  lining  mem- 
brane of  all  the  hollow  viscera  has  the  same  name,  some  con- 
fusion may  be  produced  unless  one  bears  in  mind  the  distinc- 
tion. Bordeu  has  expressed  the  character  of  the  internal 
cellular  membrane  very  forcibly  in  saying,  that  in  embryos  all 
their  organs  are  species  of  buds,  which  vegetate  in  the  cellular 
tissue,  like  plants  do  in  the  open  air,  or  their  roots  in  the  ground, 
and  that  each  one  having  an  apartment  of  its  own,  this  apart- 
ment is  to  it  a  cellular  atmosphere,  which  keeps  in  a  perfect 
relation  with  the  action  of  the  organ.J 

In  tracing  many  of  the  laminae  of  the  cellular  substance,  we 
find,  that  as  life  advances,  they  assume  a  more  fibrous  charac- 
ter than  what  they  possessed  in  infancy;  this  also  occurs  when 

*  Beclard,  Anat.  Gen.  p.  141.    Haller,  loc.  cit.  p.  19;  vol.  i.  p.  113. 

t  Loc.  cit. 

t  Loc.  cit.  p.  65.  Rechcrches  Anatomiques  sur  les  Glands,  Paris,  1752.  Also-, 
An  Exposition  of  the  Physiol.  and  Pathol.  Doctrines  of  Theoph.  Bordeu,  under-, 
stood  to  be  from  the  pen  of  a  learned  friend,  R.  La  Roche,  M.  D.,  in  the  North 
American  Med.  and  Surg.  Journal.  Philad.  April,  1826. 


324  INTEGUMENTS. 

they  are  pressed  upon  by  tumours,  or  irritated  from  many  other 
causes.  This  disposition  of  the  cellular  substance  to  assume  a 
ligamentous  character,  in  many  of  the  attachments  which  are 
formed  between  the  two  tissues,  frequently  leaves  it  doubtful 
with  which  the  membrane  under  examination  should  be  classed; 
in  some  individuals  the  fibrous  substance  is  predominant,  and 
in  others  the  cellular.  This  deposite  of  fibrous  matter  into  cel- 
lular substance,  or  rather  the  change  of  the  latter  into  it,  may 
be  compared  to  the  partial  or  even  perfect  conversion  of  the 
cartilages  of  the  thorax  into  bone  by  an  increased  deposite  of 
the  phosphate  of  lime.  It  perhaps  will  be  better  understood  by 
repeating  that  this  cellular  tissue  is  an  elementary  one,  where- 
as the  ligamentous  is  composed  of  it  and  ligament. 

In  addition  to  the  uses  of  the  cellular  substance  in  forming  a 
nidus  for  the  deposite  of  all  the  molecules  of  the  body,  and  in 
circumscribing  each  organ,  so  as  to  keep  it  distinct  from  the 
contiguous  ones  of  a  different  character,  its  elasticity  and  yield- 
ing nature  permit  it,  in  the  movements  of  the  several  parts  upon 
each  other,  to  change  its  position,  and  upon  the  cessation  of 
the  active  cause,  to  re-establish  itself.  Its  extreme  flexibility  is 
kept  up  by  a  continued  exhalation  of  moisture  from  the  arte- 
ries that  ramify  through  its  texture.  This  cellular  serosity, 
when  an  animal  is  recently  killed,  and  its  internal  parts  ex- 
posed to  a  cold  atmosphere,  rises  in  the  form  of  vapour,  and 
has  a  particular  smell.  It  is  more  abundant  in  certain  parts 
than  in  others;  and,  as  a  general  rule,  where  there  is  the  least 
adipose  matter.  Indeed,  these  two  substances  seem  to  exist  in 
an  inverse  ratio:  in  a  person,  for  example,  who  has  died  very 
fat,  the  parts  are  comparatively  dry;  whereas,  in  such  as  have 
all  the  adipose  matter  wasted  by  a  lingering  disease,  there  is  a 
humidity  which  quickly  disposes  to  putrefaction;  a  fact  fre- 
quently exemplified  in  our  dissecting-rooms.  The  cellular  se- 
rosity is,  consequently,  more  abundant  in  the  scrotum,  in  the 
eyelids,  and  in  the  penis.  Bichat  informs  us,  that  he  has  satis- 
fied himself  by  experiments,  of  its  augmentation  during  diges- 
tion, during  heavy  perspirations,  and  after  sleep;  which  will 
account  for  the  swelling  of  the  eyelids,  so  commonly  observed 
in  the  morning,  upon  rising. 

This  serosity  is  albuminous,  as  proved  by  its  being  coagu- 


ADEPS.  325 

lated  by  alcohol,  and  by  the  mineral  acids.  It  is  removed  by 
the  absorbents;  assisted  by  the  tonic  contraction  of  the  cellular 
membrane,  according  to  M.  Beclard.*  The  latter  author,  in- 
deed, goes  on  to  say,  that  the  cellular  membrane  is  the  essential 
organ  of  absorption,  by  which  the  skin  and  the  villosities  of  the 
internal  membrane  of  the  hollow  viscera  perform  this  function. 
That  the  substances  introduced  through  it  into  the  blood-ves- 
sels, no  doubt,  in  doing  so,  undergo  some  kind  of  elaboration, 
in  the  same  way  that  those  do  which  are  deposited  in  its  inter- 
stices for  the  growth,  repair,  and  changes  of  the  body. 


CHAPTER    II. 

OF  THE  FAT,  (ADEPS.) 

THE  Adeps,  in  subjects  not  much  emaciated,  is  found  be- 
neath the  skin;  between  it  and  the  fasciae;  and  in  the  layers  of 
common  cellular  substance  which  are  next  to  the  muscles;  as 
on  the  face,  the  neck,  the  trunk  of  the  body,  the  buttocks,  the 
limbs,  the  palms  of  the  hands,  and  the  soles  of  the  feet.  In  the 
adult,  it  is  also  found  between  the  serous  membranes  and  the 
cavities  which  they  line,  as  in  the  thorax  and  abdomen;  it  is 
also  found  between  the  lamina?  of  these  membranes,  as  in  the 
omenta,  mesentery,  and  so  on.  It,  likewise,  exists  between  the 
interstices  of  muscles;  in  the  hones,  and  elsewhere;  so  that  its 
whole  amount  is  estimated  at  about  one-twentieth  of  the  entire 
weight  of  the  body.  There  are,  however,  certain  portions  of 
the  body,  where  its  presence  would  have  been  very  inconve- 
nient: they,  accordingly,  are  destitute  of  it;  to  wit,  the  interior 
of  the  cranium,  of  the  ball  of  the  eye,  the  nose,  the  ear,  the  in- 
testinal canal,  the  eyelids,  the  scrotum,  the  penis,  the  labia  in- 
terna,  and  the  substance  of  the  glands. 

The  adops  is  of  a  yellowish  colour,  and  of  a  semifluid  state 
in  the  living  body:  when  after  death  it  has  got  a  few  degrees 
below  the  standard  of  animal  heat,  it  becomes  somewhat  solidi- 

*  Anat,  Gen.  p,  149. 

VOL.  I.— 28 


326"  INTEGUMENTS. 

fied,  and  then  appears  in  small  aggregated  masses  of  cfiffererrf 
shapes  and  sizes. 

In  chemical  composition  it  differs  from  all  other  parts  of  the 
body  by  the  absence  of  nitrogen,  and  is  formed  of  oxygen,  hy- 
drogen, and  carbon,  which  render  it,  in  animals,  a  very  suita- 
ble- article  for  candles  and  lamps.  According  to  the  analysis 
of  Chevreuil,*  it  consists  of  two  kinds  of  matter,  elain  and  stea- 
rin; the  former  of  which  remains  fluid  at  the  freezing  point, 
while,  as  mentioned,  the  other  becomes  solid  by  a  very  small 
abatement  of  its  living  temperature.  The  application  of  porous 
paper  enables  one  to  separate  them  in  a  small  way. 

The  adeps,  though  lodged  in  the  cellular  substance,  is  accom- 
modated there  under  different  circumstances  from  the  cellular 
serosity,  and  is  supposed  to  be  in  different  cells.  This  doctrine 
was  promulgated  by  Dr.  Wm.  Hunter,^  and  upon  the  following 
grounds:  That  certain  parts  of  the  cellular  membrane  are  des- 
titute of  it;  that  in  persons  who  have  died  from  dropsy,  the 
portions  of  the  cellular  membrane  which  originally  contained 
fat,  have  a  more  ligamentous  condition  than  others ;  to  wit,  those 
on  the  loins  next  to  the  skin,  more  than  the  stratum  next  to  the 
lumbar  fascia;  that  water  or  flui'ds  pass  readily  from  a  higher 
to  a  lower  part  of  the  cellular  membrane,  either  when  extrava- 
sated  naturally  or  injected;  that  oil,  when  injected  artificially,. 
subsides*in  the  same  way,  and  has  a  doughy  or  oedematous  feel, 
yielding  readily  to  pressure  and  pitting,  whereas,  fat  never 
shifts  its  position  simply  from  gravitation. 

From  these  several  causes,  Dr.  Hunter  adopted  the  opinion 
that  the  fat  of  the  cellular  membrane  is  lodged  in  peculiar  ve- 
sicles, and  not  as  the  water  of  anasarca,  in  the  reticular  inter- 
stices of  parts.  This  idea  has  been  adopted  by  Beclard,  who 
says  that  the  lobules  of  fat,  when  examined  with  a  microscope, 
are  seen  to  be  composed  of  small  grains  or  vesicles,  from  the 
six  hundredth  to  the  eighth  huridreth  part  of  an  inch  in  diame- 
ter, each  one  having  a  pedicle  furnished  from  the  adjacent 
blood  vessel.  That  the  parietes  of  the  vesicles  are  so  fine  as  to 
escape  observation,  but  that  he  considers  them  as  arranged  in 
the  same  way  with  the  pulp  of  oranges,  lemons,  and  such  kind 
of  fruit.  These  several  reasons  a?e  so  plausible  that  I  cannot 

*  Annalcs  de  Cliimie,  vol.  xciv. 

t  Medical  Observations  and  Inquiries.     London,  1762, 


ADEPS.  327 

but  subscribe  to  their  force  and  accuracy,  notwithstanding  the 
objection  raised  from  quarters  of  :high  authority. 

It  is  more  abundant  in  the  female  than  in  the  male,  and  in 
both  sexes  it  is  removed  as  life  declines.  In  the  infant  the  fat 
is  found  at  the  surface  of  the  body  chiefly,  little  or  none  exist- 
ing in  the  interstices  of  muscles,  and  in  the  cavities. 

Its  uses  are  not  fully  understood.  At  some  points  it  serves 
to  diminish  pressure,  as  on  the  hands  and  feet;  at  others  it  fills 
up  interstices;  it  is  also  a  bad  conductor  of  caloric,  and  may, 
therefore,  serve  in  retaining  animal  heat.  But  its  most  general 
application  is  to  the  purposes  of  nutrition,  it  being  one  of  those 
forms  which  nutritive  matter  assumes  previously  to  being  per- 
fectly assimilated.  This  is  very  fully  manifested  in  hibernating 
animals,  which  being  fat  in  the  beginning  of  their  torpid  state, 
return  from  it  quite  lean;  and  in  insects  which  during  their  re- 
pose in  the  chrysalis  state,  live  upon  their  own  fat  while  under- 
going the  metamorphosis  into  the  perfect  animal.* 

*  Beclard,  Anat  Gen.  p.  170. 


PART  If. 


Of  the  Dermoid  Covering. 

THE  Dermoid  Covering,  or  tissue  of  the  body,  consists  in.  the 
Skin; — its  Sebaceous  organs; — the  Nails; — and  the  Hair. 


CHAPTER  I. 


OF  THE  SKIN. 


THE  Skin  (Pellis,  Cutis,  hp/**)  is  extended  over  the  whole 
surface  of  the  body,  and  thereby  constitutes  a  complete  invest- 
ment of  it.  At  the  orifices  of  the  several  canals  which  lead 
into  the  interior  of  the  body,  as  the  mouth,  nose,  vagina,  anus, 
and  urethra,  it  does  not  cease  abruptly,  but  is  gradually  con- 
verted into  the  mucous  membrane  of  the  part,  so  that  it  is 
plainly  continuous  with  it.  At  certain  places,  on  the  middle 
line  of  the  body,  the  junction  of  the  skin  of  the  two  sides  is  in- 
dicated by  a  change  in  its  appearance,  called  Raphe;  as  on  the 
upper  lip;  from  the  navel  to  the  pubes;  on  the  scrotum,  and  in 
the  perineum;  in  all  of  which  places,  in  the  development  of  the 
fo3tus>  the  two  sides  of  the  body  are  later  in  uniting  than  else- 
where. 

The  colour  of  the  skin  varies  in  different  nations:  it  is  black 
in  the  negro;  of  a  copper  colour  in  the  American  savage; 
bronzed,  or  tawny,  in  the  Arabian;  and  white  in  the  Europeans 
and  their  descendants.  It  is  also  subject  to  various  shades, 
from  the  mixture  of  these  races,  and  from  the  influence  of  cli- 


THE  SKIN.  329 

mate;  its  general  tendency  being  to  turn  dark  on  parts  exposed 
to  the  influence  of  tropical  heat  and  light. 

The  external  surface  of  the  skin,  or  that  which  is  free,  has 
on  it  a  great  multitude  of  wrinkles;  some  of  them  depend  upon 
the  subjacent  muscles,  as  on  the  forehead  and  face;  some  are 
caused  by  the  flexions  of  the  articulations,  and  are  to  be  seen 
at  all  of  these  places  on  the  limbs;  in  addition  to  which,  where 
there  is  much  emaciation  of  the  parts  beneath,  the  skin  not 
having  sufficient  elasticity  to  accommodate  itself  to  their  state, 
is  thrown  into  other  wrinkles,  and  sometimes  into  loose  folds. 
Finer  wrinkles  of  another  description  are  also  found  on  the 
skin,  arranged  in  various  angular  and  spiral  directions:  they 
depend  on  an  entirely  different  cause,  which  will  be  treated  of 
elsewhere. 

The  skin  abounds  in  hairs,  which  vary  in  fineness  and  in 
length  according  to  the  region  over  which  they  are  distributed : 
it,  likewise,  presents  many  small  pits,  or  follicles,  which  are 
the  orifices  of  sebaceous  glands.  A  finer  description  of  pores, 
which  are  visible  only  to  the  assisted  eye,  are  supposed  to  be 
the  orifices  of  exhalents  and  of  absorbents,  but  this  is  not  quite 
certain. 

The  internal  surface  of  the  skin  is  connected  to  the  subja- 
cent parts  by  the  cellular  tissue,  which  permits  a  considerable 
sliding  of  it  backwards  and  forwards  on  most  parts  of  the 
body;  on  others,  however,  this  is  restrained,  as  on  the  cranium, 
the  palms  of  the  hands,  and  the  soles  of  the  feet,  by  ligamen- 
tous  fibres  passing  to  it  from  the  fascia3  and  bones  below.  A 
very  interesting  attachment  of  this  kind  exists  on  the  fingers, 
where  a  plane  of  ligamentous  fibres  is  seen  passing  from  each 
side  of  the  lower  end  of  the  first  phalanx,  downwards,  to  be 
inserted  into  the  skin,  half  an  inch  or  an  inch  off. 

Since  the  first  observation  of  Malpighi,  on  the  tongue  of  a 
bullock,  whereby  he  ascertained  that  its  integuments  consisted 
in  three  layers,  and  the  discovery  of  a  similar  arrangement  on 
other  portions  of  the  integuments  by  Ruysch,*  anatomists  have, 
for  tho  most  part,  admitted  the  skin  to  consist  of  three  lamince, 
the  Cuiis  Vera,  the  Rete  Mucosum,  and  the  Cuticula. 

*  Thesaurus,  Anat.  IX. 
28* 


330  INTEGtJMENtS. 


SECT.  I. OF  THE  CUTIS  VERA. 

The  True  Skin  (cutis  vera,  derma,  corion,)  is  the  deepest,  of 
the  layer  next  to  the  cellular  substance.  Its  thickness  varies 
according  to  age,  sex,  and  the  region  of  the  body  over  which  it 
is  stretched;  on  the  trunk  it  is  thicker  behind  than  it  is  in  front; 
on  the  limbs,  thicker  on  their  external  than  on  their  internal 
faces  or  semi-circumferences.  On  the  mammae,  the  penis,  scro- 
tum, and  external  ear,  its  tenuity  is  remarkable.  When  unin- 
jected,  it  is  perfectly  white  in  people  of  all  complexions,  and  in 
the  living  state  has  a  semi-transparency  that  permits  the  blood 
of  the  veins  to  be  seen  beneath  it. 

The  internal  surface  of  the  true  skin  is  so  blended  with  the 
cellular  substance,  that  in  the  recent  subject  there  is  a  difficul- 
ty in  distinguishing  where  one  terminates  and  the  other  begins, 
yet  they  may  be  separated  by  maceration  so  as  to  determine 
this  line  ;  mortification  of  the  cellular  substance  sometimes  does 
the  same  thing;  and  in  the  ham,  cured  by  salting  and  smoking, 
the  true  skin,  after  boiling,  may  be  stripped  off  with  but  little 
difficulty.  In  either  of  these  cases  the  internal  surface  of  the 
latter  is  seen  to  be  studded  with  small  areolar  depressions, 
caused  by  the  projection  of  granulated  masses  of  adeps;  the 
margins  of  those  alveoli  are  the  principal  points  of  adhesion 
to  the  subcutaneous  cellular  tissue,  while  their  bottoms  are 
pierced  with  small  openings  that  lead  through  the  skin. 

The  external  surface  of  the  true  skin  is  covered  with  very 
fine  papillae,  or  villi,  (Papillce  Tactus,)  that  are  readily  brought 
within  the  observation  of  the  naked  eye,  by  maceration,  when 
protracted  long  enough  to  permit  the  separation  of  the  cuticle. 
The  projections  on  the  tongue  are  very  similar  to  them,  and 
the  whole  are  designated  as  the  papillary  body.  These  cuta- 
neous papillae  are  particularly  distinct  at  the  bulbous  ends  of 
the  fingers  and  toe?,  upon  the  palms  and  soles,  on  the  lips,  on 
the  glans  penis,  and  the  nipple;  in  other  parts  they  are  not  so 
evident,  but  still  there  can  be  no  doubt  of  their  existence,  from 
analogy.  On  the  hands  and  feet  they  are  arranged  in  double 
rows  or  files,  which  occasion  the  semicircular  and  spiral  turns 


CUTIS  VERA.  331 

of  small  wrinkles  or  ridges  at  the  ends  of  the  fingers  and  toes ; 
and  the  transverse  oblique,  and  curved  ones,  on  other  parts  of 
the  soles  and  palms.  The  small,  triangular,  lozenge-shape,  and 
multangular  elevations  of  the  cutis  vera,  seen  elsewhere  on  it* 
external  surface,  are  caused  rather  by  its  contraction  than  by 
the  papillae. 

These  papillary  projections  resemble  very  much  small  conoi- 
dal,  cotton-like  filaments,  standing  up  the  twelfth  of  a  line,  or 
thereabouts,  from  the  surface  of  the  skin:  they  are  by  no  means 
so  long  as  the  villi  generally  of  the  intestines,  and,  like  them, 
consist  in  very  delicate  ramifications  of  nerves  and  blood  ves- 
sels, united  by  cellular  tissue.  In  places  where  these  papillae 
are  less  abundant,  the  cutis  vera  is  not  so  vascular  or  sensitive. 
They  readily  receive  a  fine  injection,  and,  if  the  cuticle  be 
afterwards  separated  by  maceration,  their  vascularity  is  very 
distinct.  Their  nerves  are  destitute  of  neurileme.* 

The  texture  of  the  true  skin  is  fibrous;  the  fibres  which  com- 
pose it,  by  their  irregular  intermixture,  resolve  it  into  a  mass 
of  net-work  or  areolae,  the  meshes  of  which  are  sufficiently 
large  in  some  parts  to  permit  the  introduction  of  the  he-ad  of  a 
small  pin.  The  meshes,  though  they  are  larger  and  more  dis- 
tinct on  the  internal  fhan  on  the  external  surface  of  the  true 
skin,  open,  however,  upon  the  latter  surface;  having  passed 
through  the  skin  obliquely,  after  the  manner  of  the  ureters 
through  the  coats  of  the  bladder.  Those  intervals  between 
the  fibres  of  the  skin  are  rendered  very  obvious  after  mace- 
ration of  a  month  or  two,  or  after  skin  has  been  tanned. 
They  serve  to  transmit  hairs,  bloodvessels,  nerves,  absorbents, 
and  exhalent  vessels  also  if  such  exist.  These  interstices  com- 
municate freely  with  the  cellular  substance,  for  in  many  cases 
of  anasarca,  blisters,  when  made  upon  a  depending  part, 
empty  the  cellular  membrane  of  water  almost  as  quickly  as 
scarifications;!  but  if  the  blisters  inflame,  they  discharge  incon- 
siderably, owing  to  the  porosities  being  shut  up  by  the  tume- 
faction and  fulness  of  the  parts.  The  same  is  observable  in 
scarifications. 

A  fine  injection,  when  forcibly  driven  into  the  extremities  of 

*  Beclard,  Anat.  Gen.  t  \V.  Hunter,  loc.  cit. 


332  INTEGUMENTS. 

a  foetus,  will  become  extravasated  between  the  cutis  vera  and 
cuticle,  and  raise  up  the  latter  in  small  blisters,  as  I  have  fre- 
quently experienced,  though  it  cannot  be  caused  to  pass  through 
the  cuticle. 

The  precise  nature  of  the  tissue  which  composes  the  true  skin 
is  not  yet  fully  ascertained;  it  seems,  however,  to  be  a  mixture 
of  cellular  substance  and  ligamentous  matter;  with  a  striking 
predominance  of  the  latter  in  most  parts  of  the  body,  though 
its  proportion  varies  considerably,  being  very  abundant  on  the 
thickest  parts  of  the  skin,  while  it  is  scarcely  discernible  on 
the  thinnest.  The  following  analogies  of  dermoid  with  liga- 
mentous or  desmoid  tissue  are  observable.  It  becomes  yellow 
and  transparent  on  being  boiled,  and  a  continuation  of  the 
process  dissolves  it  into  gelatine.  It  resists  putrefaction  for  a 
long  time;  is  remarkably  tenacious.  Contrary,  however,  to  li- 
gamentous matter,  it  is  extensible  and  elastic,  though  this  pro- 
perty may  arise  from  the  oblique  intertexture  of  its  fibres ;  as  a 
bandage  from  a  piece  of  muslin,  when  torn  longitudinally  or 
transversely,  is  inelastic,  but  if  it  be  cut  bias,  it  is  then  very 
elastic.  The  application  of  tannin  increases  its  resistance,  and 
makes  it  one  of  the  strongest  animal  substances  known  in  hu- 
man arts. 

The  skin  has  a  very  strong  power  of  contraction,  which  is 
manifested  in  an  amputation,  in  a  long  incised  wound,  or  when 
a  sensation  of  chillness  exists,  as  in  an  ague  or  from  the  appli- 
cation of  cold.  Owing  to  the  diminution  in  size  of  its  areolae, 
its  external  surface  then  becomes  wrinkled,  rough,  and  studded 
with  projecting  points,  constituting  the  Cutis  Anserina. 

The  cutis  vera  is  very  vascular,  and  abounds  also  in  nerves 
and  absorbents. 

SECT.  II. OF  THE  RETE  MUCOSUM. 

The  Mucous  Net  (Rete  Mucosum*)  of  Malpighi,  is  the  second 
layer  of  the  skin,  and  is  that  in  which  resides  the  colour  of  the 
several  races  of  men.  It  covers  every  part  of  the  surface  of 
the  cutis  vera;  its  existence,  however,  is  not  so  obvious  beneath 
the  nails  and  about  the  junction  of  the  skin  with  mucous  mem- 

*  Caldani,  Icon.  Anat.  PI.  xci.  Albinus,  Annot.  Acad.  Ley  den,  1756. 
Ruysch,  Thes.  Anat.  ix. 


RETE  MUCOSUM.  333 

branes,  as  it  is  elsewhere ;  though  taking  all  things  into  consi- 
deration, it  is  probable  that  it  exists  also  at  these  several  places* 
but  much  finer.  It  is  so  extremely  thin,  and  of  such  a  soft  muci- 
laginous consistence,  that  it  is  difficult  to  separate  it  as  a  distinct 
lamina,  either  by  maceration  or  by  any  other  means ;  for  it  most 
commonly  peels  off  by  adhering  to  the  cuticle,  after  the  man- 
ner of  a  pigment.  It,  however,  by  good  management,  may  be 
fairly  raised  as  a  membrane,  and  separated  for  a  certain  dis- 
tance from  the  other  two  coats  of  the  skin. 

Fine  as  this  membrane  is,  it  would  seem,  from  the  observations 
of  Mr.  Cruikshank*  upon  a  negro  dead  from  small-pox,  and  upon 
an  injection  executed  in  London,  by  the  late  Dr.  Baynham,  of 
Virginia,!  and  from  more  recent  experiments  in  Paris,  by  M. 
Gaultier,J  that  it  consists  in  several  layers.  1.  Upon  the  in- 
equalities or  papilla?  of  the  cutis  vera,  there  is  a  layer  called,  by 
M.  Gaultier,  bloody  pimples,  (Bourgeons  Sanguins,)  but  which, 
in  the  opinion  of  some  other  anatomists,  are  only  the  papillae 
themselves  of  the  cutis  vera.  2.  Then  there  is  a  very  thin  and 
transparent  coat,  called,  from  its  colour,  Tunica  Albida  Pro- 
funda:  it  is  especially  visible  in  the  negro;  under  the  coloured 
horns  and  scales  of  animals,  and  beneath  the  nails  of  white  per- 
sons. 3.  Over  this  layer  is  spread  another,  (the  Gemmula,) 
which  contains  the  colouring  matter  of  the  several  complexions 
of  the  human  family,  and  consists  in  a  multitude  of  dark  brown 
points  in  the  negro ;  it  is  visible  also  in  those  forms  of  disease 
called  ephelides  (freckles,)  by  the  French,  where  the  skin  be- 
comes spotted;  it  is  not  so  distinct  in  the  healthy  state  of  the 
white  individual.  4.  The  last  lamina  of  rete  mucosum,  is  called, 
by  M.  Gaultier,  Tunica  Albida  Superficialis,  from  its  whiteness 
and  superficial  situation :  in  many  animals  it  is  very  distinct, 
in  the  negro  somewhat  so,  but  in  the  white  it  is  not  to  be  seen 
except  under  the  nails,  about  the  hair,  and  under  accidental 
horny  excrescences. 

These  observations  of  M.  Gaultier  have  been  verified  by  M. 
Dutrochet,§  in  experiments  upon  the  texture  of  the  skin  of  ver- 

*  Expts.  on  Perspiration.     London,  1795. 
t  Wistar's  Anat.  vol.  i.  p.  394. 

t  Recherches  sur  la  peau,  Paris,  1809;  in  Anat.  De  L'Homme,par  J.  Cloquet. 
PI.  cxvu. 

§  Journal  de  Physique,  May,  1819.     Journal  Complementaire,  vol.  v. 


334  INTEGUMENTS. 

tebrated  animals;  and  are  now  generally  acknowledged  by  the 
French  anatomists.  In  negroes,  in  cutting  through  the  skin  of 
the  sole  of  the  foot,  from  heel  to  toe  perpendicularly  to  the  fur- 
rows, this  arrangement  is  readily  recognised;*  and  when  it  has 
become  indistinct,  it  may  be  improved  by  immersing  the  skin 
for  three  or  four  days  in  lime-water,  or  a  solution  of  potash  or 
barytes,  and  afterwards  keeping  it  the  same  length  of  time  in  a 
solution  of  corrosive  sublimate.  Blisters  also  elucidate  this 
point  on  other  parts  of  the  body:  the  fluids  being  locally  at- 
tracted there,  infiltrate  the  rete  mucosum,  and  separate  in  part 
its 'layers,  so  as  to  form  a  vesicle  frequently  very  thick,  parti- 
cularly in  fat  persons. 

The  scrotum  of  the  negro  is  also  well  suited  to  the  exhibition 
of  the  rete  mucosum,  as  it  is  there  very  distinct,  and  is  univer- 
sally much  thicker  and  better  marked  in  the  negro  than  in  any 
other  race.  From  its  extreme  tenuity  in  the  whites  its  existence 
in  them  has  by  some  persons  been  doubted,  but  erroneously,  as 
in  them  also  its  change  of  colour,  from  the  influence  of  the  sun, 
is  readily  demonstrated.  There  are  in  fact  few  persons,  perhaps 
none,  so  white,  but  what  a  slight  tinge  of  yellow  exists  in  their 
skins;  which  may  be  proved  by  contrasting  them  with  any  per- 
fectly white  surface,  as  snow,  bleached  paper,  or  linen.  This 
slight  tinge  of  yellow  is  increased  to  an  olive  colour  by  the  sun's 
rays,  and,  in  some  instances  by  a  spontaneous  deposite;  in  other 
cases,  it  is  in  certain  spots  removed,  so  as  to  leave  a  colour  al- 
most perfectly  white,  or  that  only  of  the  cutis  vera.t  When  the 
latter  change  occurs  in  the  African,  it  occasions  a  hideous  pie- 
bald complexion,  and  the  cuticle  is  readily  elevated  into  blisters, 
by  the  irritation  of  the  solar  rays.  Some  persons  have  an  entire 
deficiency  of  this  pigment  on  the  skin,  from  birth;  the  same  de- 
ficiency occurs  in  the  eyes,  and  hair;  they  are  designated  as  al- 
binos. The  deficiency  of  the  pigmentum  nigrum  in  the  eye, 
causes  it  to  look  red,  like  that  of  the  white  rabbit;  and  also 
makes  it  intolerant  of  a  strong  light,  as  that  of  noon-day. 

"  In  some  very  remarkable  instances  the  skin  becomes  entire- 
ly black.  We  have  read  to  the  Society  of  Medicine  of  the  Fa- 

*  J.  Cloquet,  Anat.  De  L'Homme.     PI.  cxvi.  Fig.  6. 

f  A  case  of  this  kind  is  now  in  the  Philadelphia  Alms  House,  where  the  ab- 
sorption of  colour  has  occurred  in  spots  on  the  hands  of  a  dark-complexioned  Eu- 
ropean. June  15, 


RETE  MUCOSUM.  335 

culty,  the  history  of  a  woman  whose  skin  became  black  in  the 
period  of  a  night,  in  consequence  of  a  strong  moral  impression. 
This  woman  had  seen  her  daughter  throw  herself  out  of  the  win- 
dow with  her  two  little  children;  and  we  have  since  had  occa- 
sion to  see,  also,  a  woman,  who  having  escaped  capital  punish- 
ment, in  the  revolution,  had  experienced  the  same  accident.  The 
latter  was  at  the  period  of  menstruation  when  she  learned  this 
news.  The  menses  were  immediately  suppressed,  and  from 
white,  which  she  was,  she  became  black  as  a  negress,  which 
colour  continued  even  to  her  death.  We  dissected  with  care 
the  skin  of  these  two  women,  and  found  the  coloured  portion  to 
be  the  rete  mucosum.  We  found  it  sufficiently  easy  to  isolate 
the  epidermis  and  the  dermis,  which  presented  no  abnormal  co- 
loration. This  black  colour  must  be  the  result  of  a  sanguineous 
exhalation  which  operates  upon  the  rete  mucosum. 

"  The  violet  tinge  of  the  skin  is,  ordinarily,  the  result  of  em- 
barrassed circulation.  The  skin  becomes  blue  in  many  very  ad- 
vanced diseases  of  the  heart.  The  name  of  Cyanosis,  or  blue 
disease,  has  been  given  to  this  colour  of  the  skin,  which  is  falsely 
attributed  to  an  immediate  communication  of  the  auricles  by 
means  of  the  unobliterated  foramen  ovale.  This  cause  of  the 
cyanosis  is  much  more  rare  than  is  commonly  supposed."* 

The  pigment  of  the  rete  mucosum  would  seem,  for  the  fore- 
going reasons,  to  be  continually  undergoing  a  deposition  and  ab- 
sorption. When  it  has  been  lost  by  a  blister  in  an  African,  it 
is  generally  restored  in  a  short  time  afterwards:  the  same  oc- 
curs in  their  cicatrices,  but  requires  a  longer  period.  The  ob- 
servations of  chemists  tend  to  prove  that  it  is  formed  principal- 
ly by  carbon.  Its  apparent  use  is  to  defend  the  skin  from  the 
rays  of  the  sun,  in  illustration  of  which  several  ingenious  ex- 
periments have  been  executed  by  Sir  Everard  Home.f 

The  influence  of  the  continued  use  of  nitrate  of  silver,  in 
giving  a  lead  colour  to  the  skin  is  well  known.  Anatomists 
generally  have  rejected  the  idea  of  the  vascularily  of  the  rete 
mucosum,  yet  it  would  seem  to  have  been  injected,  on  one  oc- 
casion at  least  by  the  late  Dr.  Baynham,  in  a  leg  which  was 


*  Cours  de  Medecine  Clinique,  par  Leon  Rostan.     Paris,  1830. 
f  Philos.  Transact.  London,  1821. 


336  INTEGUMENTS. 

diseased  from  exostosis;*  and  there  are  now  in  the  anatomical 
cabinet  of  the  University,  three  preparations  by  myself  of  the 
fingers  of  an  African,  where  the  colouring  matter  of  the  injec- 
tion has  been  passed  from  the  papillae  of  the  cutis  vera  into  the 
rete  mucosum ;  and  there  deposited  in  dots,  indicating  the  for- 
mer position  of  the  papilla?. 


SECT.  III. — OF  THE  CUTICLE  (CUTICULA.) 

The  Cuticle  or  Epidermis,  is  the  most  superficial  layer  of  the 
skin,  and  takes  its  wrinkles  from  the  closeness  of  its  applica- 
tion to  the  true  skin.  It  is  a  thin,  dry  pellicle,  which  cannot 
be  separated  from  the  cutis  by  dissection;  in  consequence  of 
which  we  have  to  resort  to  the  alternate  application  of  hot  and 
cold  water;  to  partial  putrefaction ;  or  in  the  living  body  to 
vesicatories.  The  mode  of  adhesion  between  the  cuticle  and 
the  true  skin  is  not  precisely  understood:  the  surfaces  unques- 
tionably adhere,  through  the  intervention  of  the  rete  mucosum, 
with  equal  tenacity  where  there  are  neither  hairs  nor  sebaceous 
follicles  to  pin  them  together,  as  on  the  palms  of  the  hands  and 
soles  of  the  feet;  and  when  by  previous  management  this  union 
is  somewhat  softened,  they  part  very  much  after  the  manner 
of  two  sheets  of  paper,  which  had  been  recently  glued  and 
were  almost  dry.  From  this  it  would  appear  that  the  adhe- 
sion is  universal,  and  not  defective  at  any  points. 

In  most  parts  of  the  body  the  cuticle  presents  itself  MS  a  sin- 
gle homogeneal  layer,  of  a  thickness  uniformly  about  that  of 
the  thinnest  Chinese  blotting  paper.  Upon  the  palms  and  soles 
of  persons  generally,  but  especially  of  such  as  are  addicted  to 
heavy  labour,  and  exposed  to  a  continued  mechanical  irrita- 
tion of  these  parts,  the  cuticle  becomes  much  thickened  and 
laminated,  apparently  from  a  successive  deposite  of  it  on  the 
skin,  there.  It  is  transparent,  by  which  the  colour  of  the  parts 
beneath  is  readily  discernible;  in  the  African,  however,  it  is 
extremely  difficult,  nay,  impossible  to  clean  it  wholly  of  the 
colouring  matter  of  the  rete  mucosum;  it  seems  indeed  as  if  it 
were,  according  to  the  opinion  of  some,  impregnated  by  it. 

*  Mec&el  speaks  familiarly  of  its  being  furnished  with  an  innumerable  quanti- 
ty of  capillary  vessels.  Vol.  i.  p.  470. 


CUTICLE.  337 

The  structure  of  this  body  is  entirely  peculiar;  there  is  no 
evidence  whatever  of  the  existence  of  vessels  in  it:  on  the  con- 
trary, in  inflammations,  when  the  skin  becomes  of  the  deepest 
tinge  of  red,  the  epidermis  never  has  its  colour  changed  in  the 
smallest  degree;  the  impression  made  on  it  is  only  manifested 
by  its  dropping  off,  while  another  layer  is  preparing  to  take  its 
place. 

Dr.  W.  Hunter,  though  he  disbelieved  in  the  possibility  of 
injecting  the  cuticle,  and  did  not  admit  the  evidence  of  the 
preparations  of  his  time  having  that  reputation ;  yet  thought  the 
communicating  or  perspiratory  vessels  might  be  exhibited  in  a 
different  manner,  that  is,  by  macerating  for  a  short  time  a  piece 
of  the  sole  of  the  foot :  afterwards,  in  separating  the  cuticle 
from  the  cutis  vera,  as  the  two  membranes  parted,  these  vessels 
would  be  found  in  the  angle  of  separation  passing  from  one  to 
the  other  like  cob-web  filaments.* 

There  can  be  no  doubt  of  the  accuracy  of  this  statement, 
for  it  is  easily  verified  by  any  one  who  will  take  the  trouble 
to  perform  the  experiment;  yet  it  is  more  than  probable  that 
Dr.  Hunter  was  deceived  in  the  nature  of  these  filaments,  and 
that  as  M.  Beclard  has  suggested,  they  were  merely  the  threads 
formed  out  of  the  rete  mucosum,  which  was  rendered  a  viscous 
fluid  by  the  commencement  of  putrefaction;  and,  therefore, 
when  parted,  would  put  on  the  same  filamentous  appearance, 
that  half  dissolved  glue  does  in  a  similar  situation.  Some  of 
the  aforesaid  filaments  also  are  supposed  by  Bichat  and  Chaus- 
sier  to  be  absorbents;  but  this  opinion  of  course  sinks  with  the 
objections  brought  against  Dr.  Hunter. 

Neither  is  there  any  evidence  of  the  existence  of  nerves  or 
of  the  cellular  membrane  in  this  tissue;  for  it  is  in  all  states 
entirely  devoid  of  sensibility,  and  never  puts  forth  granulations. 
The  excrescences  which  belong  to  it,  as  corns  and  indurations, 
are,  like  it,  laminated,  owing  to  their  thickness,  and  have  no 
interior  circulation;  and  though  sometimes  painful,  are  so  only 
by  their  pressing  upon  the  subjacent  nerves  of  the  skin.  It  is 
also  destitute  of  filaments. 

•The  cuticle  is  penetrated  by  hairs,  and  by  the  orifices  of  the 
sebaceous  follicles  and  glands;  and  according  to  Bichat,  also, 

*  Mcd.  Obs.  and  Inquiries,  vol.  ii.  p.  53,  London,  1762. 
VOL.  I.— 29 


338  INTEGUMENTS. 

by  the  exhalents  and  absorbents,  the  several  orifices  of  which' 
he  says  become  distinct  by  holding  it  between  the  eye  and  a 
strong  light.  As  it,  when  raised  by  a  blister,  does  not  allow 
the  effused  fluid  to  pass  through  any  of  these  pores,  it  is  very 
reasonably  supposed  that  they  are  all  oblique,  and  therefore 
exercise  a  valvular  office  on  such  an  occasion.  Or  if,  accord- 
ing to  the  supposition  of  Mr.  Cruikshank,  the  finest  pores  of  the 
cutis  vera  are  lined  by  processes  from  the  cuticle,  the  collapse 
of  these  processes  on  the  separation  of  the  cuticle  will  also  ac- 
count for  the  fact.  It  seems  to  be  well  ascertained  at  the  pre- 
sent time,  that  as  the  epidermis  is  more  transparent  at  certain 
points  than  elsewhere,  the  appearance  has  been  mistaken  for 
porosities  of  exhalents  and  sbsorbents.  The  cuticle,  when  de- 
tached, will  not  allow  a  column  of  mercury  to  pass  through  ity 
except  its  weight  be  so  great  as  to  lacerate  it :  this  fact  is  ra- 
ther against  the  doctrine  of  the  pores  being  visible  when  exa- 
mined by  permitting  the  light  to  shine  through,  and  shows  that 
even  those  for  the  hairs  and  the  sebaceous  follicles  are  stopped 
by  some  arrangement  or  other.  Upon  the  whole,  the  opinion 
of  organized  pores  in  the  cuticle  for  exhalation  or  absorption, 
is  not  sustained  by  unobjectionable  testimony,  and  is  scarcely 
admissible  upon  any  principle.  At  the  same  time  it  maybe  re- 
marked, that  the  interstices  which  exist  in  it  would  seem  to  be 
sufficient  to  account  for  many  of  the  phenomena  of  exhalation 
and  of  absorption. 

The  cuticle  has  but  little  power  of  extension,  and,  conse- 
quently of  contraction,  and  tears  with  the  application  of  a  very 
slight  force.  It  naturally  contains  so  little  moisture,  that  its 
bulk  is  only  inconsiderably  altered  by  drying.  Ir,  like  the  hair 
or  nails,  resists  putrefaction  so  much,  that  it  has  been  found  in 
burial  places  after  a  lapse  of  fifty  years.  When  held  in  water, 
it  swells,  becomes  white,  wrinkles  more,  loses  its  transparen- 
cy, and  dulls  the  sensibility  of  the  cutaneous  papilla?.  It  can- 
not, like  the  true  skin,  be  readily  reduced  by  boiling  water  into 
gelatine,  and  consequently,  is  not  affected  by  tanning:  it,  in- 
deed, retards  that  process,  when  left  on  the  proximate  surface 
of  the  cutis  vera.  When  applied  to  a  fire,  it  burns,  like  the 
hair  and  nails,  wilh  extreme  facility,  owing  to  the  presence  of 
a  similar  oil  in  it,  and  it  gives  out  a  very  disagreeable  odour. 

The  little  extensibility  of  the  cuticle  causes  it  to  be  ruptured 


aao 

whenever  tumours,  as  warts,  &c.,  rise  from  the  surface  of  the 
cutis  vera:  it  is  supposed,  however,  not  to  be  entirely  deprived 
of  this  quality,  as  it  seems  to  stretch  when  raised  into  a  blister, 
though  this  may  arise,  in  some  measure,  from  the  small  wrinkles, 
naturally  existing  in  it,  being  drawn  out.  It  has  not  the  slightest 
sensibility,  neither  is  this  quality  evolved  by  any  condition 
whatever,  as  it  is  in  tendons,  ligaments,  and  bones,  when 
they  become  inflamed. 

There  is,  in  all  probability,  a  slow  loss  and  reproduction  of 
the  cuticle  constantly  going  on,  The  former  is  manifested  by 
the  large  quantity  of  branny  scales  that  are  detached  from  its 
surface,  when  one  has  abstained  from  bathing  for  a  long  time. 
This  is  more  remarkable  on  the  palms  and  soles  than  elsewhere., 
and  the  loss  must,  of  course,  be  continually  supplied.  It,  as  is 
well  known,  is  rapidly  regenerated  when  it  has  been  lost  sim- 
ply by  an  abrasion  or  blistering,  which  has  not  interfered  with 
the  organization  of  the  rete  mucosum.  In  some  cases  there  is 
an  unusual  development  of  it :  Bichat  retained  the  skin  of  a 
patient,  dead  at  the  Hotel  Dieu,  in  whom  the  cuticle,  at  the  pe- 
riod of  birth  and  in  subsequent  life,  was  three  times  the  natural 
thickness;  and  had  always,  with  the  exception  of  that  of  the 
face,  been  subject  to  a  continual  desquamation. 

As  the  epidermis  has  in  itself  no  power  of  regeneration,  ow- 
ing to  its  deficient  organization,  the  most  plausible  opinion  in 
regard  to  its  source  is,  that  it  is  produced  by  the  inspissation 
and  drying  either  of  the  external  layer  of  the  rete  mucosum  or 
of  a  secretion  from  it,  which  renders  it  a  sort  of  varnish,  well 
qualified  to  resist  the  agency  of  exterior  objects,  and  to  protect 
the  delicate  organization  of  the  proximate  surface  of  the  cutis 
vera.  This  opinion  of  its  origin  seems  to  be  proved  by  its  par- 
ticipating in  the  colour  of  the  rete  mucosum,  more  or  less,  so 
as  to  give  it  a  sensible  tinge,  which  cannot  be  washed  from  it. 

One  of  the  most  striking  properties  of  the  cuticle  is  its  re- 
sistance to  evaporation  from  the  surface  of  the  body :  in  a  sub- 
ject, any  part  of  the  derm,  when  deprived  of  it  and  exposed  to 
the  air,  dries  up  in  the  course  of  a  day  or  two,  while  the  other 
portions  remain  soft  and  flexible  for  weeks,  and,  if  it  were  not 
for  putrefaction  causing-  the  cuticle  to  peel  off,  would  some- 
times remain  so  for  months.  Though  it  suppresses  evapora- 


340  INTEGUMENTS. 

tion,  in  a  great  measure,  it  does  not  do  so  entirely  ;  for,  after 
a  subject  has  been  kept  some  time,  its  fingers,  toes,  nose,  and 
ears  get  very  dry  and  hard. 

During  life  the  process  of  perspiration  is  continually  going 
on,  either  in  a  sensible  or  insensible  manner;  and  according  to 
the  experiments  of  Sanctorius,  more  than  one-half  of  the 
weight  of  our  food  is  lost  in  that  way  through  the  skin  and 
lungs.  MM.  Lavoisier  and  Seguin  ascertained  that  the  propor- 
tionate exhalation  from  these  organs  was  eleven  of  the  former 
to  two  of  the  latter.  When  the  perspiration  is  rapid,  it  assem- 
bles on  the  surface  of  the  body  in  the  form  of  small  drops, 
having  an  acid,  saltish  taste,  and  a  peculiar  odour.  In  this 
state,  according  to  the  analysis  of  Berzelius,  it  consists  princi- 
pally in  water,  holding  in  solution  a  hydrochlorate  of  soda  and 
of  potash,  some  lactic  acid,  lactate  of  soda,  and  a  little  animal 
matter.  The  perspiration,  besides  its  use  as  an  excretion,  is 
a  powerful  means,  by  it«s  evaporation,  of  enabling  the  body 
to  resist  a  high  temperature.  It  varies,  both  in  quality  and 
quantity,  according  to  age,  sex,  state  of  health,  food,  and  habits 
offife. 

The  power  of  the  cuticle  to  absorb  or  to  transmit  inwardly 
articles  through  it,  is  not  by  any  means  so  obvious  as  its  exha- 
lation: the  facts,  however,  upon  the  whole,  seem  to  prove  that 
though  this  power  is  much  curtailed  when  compared  with  that 
possessed  by  mucous  surfaces,  yet  it  does  exist  to  a  certain  ex- 
tent.* 


CHAPTER  II. 

OF  THE  SEBACEOUS  ORGANS  OF  THE  SKIN. 

THE  Sebaceous  Organs  consist  in  Follicles  (Cryptce,  Mucosa) 
and  Glands,  (Glandules  Sebacece.)  They  furnish  the  oily  exha- 
lation, which  lubricates  the  surface  of  the  skin,  gives  linen, 
when  worn  a  long  time,  a  greasy  appearance,  and  causes  the 

A 

*  Wistar's  Anat.  Vol.  ii.  p.  396,  3d  edit. 


THE  SEBACEOUS  ORGANS.  341 

water  in  which  we  bathe  to  assemble  in  drops,  on  the  surface 
of  the  body,  rather  than  to  wet  it  uniformly.  This  humour 
produces  a  rancid  disagreeable  smell  in  negroes,  and  such  per- 
sons as  do  not  resort  to  ablutions  of  the  whole  skin,  from  time 
to  time.  It  is  particularly  abundant  about  the  places  provided 
with  hairs,  as  the  scalp,  the  genital  organs,  the  axillce,  and 
seems  to  be  intended  to  maintain  the  flexibility  and  smoothness 
of  the  skin  and  hair,  and  to  prevent  the  former  from  chapping. 
These  qualities  of  it  are  possessed,  in  a  considerable  degree, 
by  the  oily  articles  of  the  toilet,  which  are  used  for  the  same 
purpose.  There  can  be  no  doubt  of  the  unctuous  quality  of 
this  secretion,  as,  when  collected  on  a  piece  of  clothing  or  on 
blotting-paper,  it  burns  with  a  white  .flame.  Its  quantity  is 
readily  augmented  by  certain  kinds  of  clothing,  which  most 
persons  must  have  observed  shortly  after  putting  on  a  flannel 
shirt  next  to  the  skin. 

It  is  sufficiently  certain  that  the  apparatus  producing  this  oil 
is  not  visible  to  the  naked  eye  in  most  parts  of  the  skin,  so  that 
there  would  seem  to  be  a  necessity  of  accounting  for  its  ap- 
pearance there,  in  some  other  way  besides  a  distinct  glandular 
apparatus.  Bichat  considered  it  to  arise  from  a  set  of  exha- 
lents  differing  from  those  which  secrete  the  matter  of  perspira- 
tion, a  theory  far  more  rational  than  that  which  attributes  it  to 
the  percolation  of  the  subcutaneous  fatty  matter.  M.  Beclard, 
however,  admits  that  sebaceous  follicles  exist  over  the  whole 
surface  of  the  skin,  with  the  exception  of  the  palms  and 
soles;  because  the  skin  is  universally  rendered  unctuous  by  this 
discharge:  many  follicles  exist,  which  are  only  visible  to  the 
microscope;  and  because  morbid  changes  frequently  render 
them  evident,  where  their  existence  was  not  suspected  before- 
In  many  places  these  follicles  are  sufficiently  obvious  and  very 
numerous,  as  on  the  nose,  about  the  corners  of  the  mouth,  on 
the  ear  and  behind  it,  and  on  the  face,  generally,  of  some  indi- 
viduals. When  the  skin  has  been  injected,  they  are  found  to 
consist  of  small  pouches  placed  in  its  thickness  and  having 
their  parietes  abundantly  furnished  with  blood  vessels. 

The  discharge  from  them  sometimes  becomes  inspissated,  and 
does  not  readily  pass  through  their  orifices;  in  which  case,  con- 
tinuing to  accumulate,  it  will,  finally,  form  a  sensible  tumour. 
Most  frequently  it  does  not  collect  to  such  an  exten%  but  is 


342  INTEGUMENTS. 

indicated  simply  by  a  small  black  point,  owing  to  the  adhesion 
of  dirt  to  it:  in  this  condition,  when  squeezed  out,  it  assumes  a 
small  vermicular  shape. 

The  Sebaceous  Glands,  properly  speaking,  are  about  the 
size  of  a  millet  seed,  of  a  light  yellow  colour,  and  are  placed, 
wherever  they  exist,  immediately  under  the  cutis  vera.  They 
are  particularly  numerous  under  the  skin  of  the  mons  veneris. 
1  have  not  observed  them  so  distinctly  elsewhere. 


CHAPTER  III. 

OF  THE  NAILS. 

THE  nails  (Ungues)  supply  the  place  of  cuticle  on  the  ex- 
tremities of  the  fingers  and  toes,  and  may  be  considered  as  a 
continuation  of  this  membrane,  because  in  maceration  they 
come  off  along  with  it.  They  correspond  with  the  talons  and 
hoofs  of  the  lower  orders  of  animals. 

Each  nail  consists  of  a  root,  of  a  body,  and  of  a  free  ex- 
tremity, or  that  which  projects  and  requires  paring.  The 
root  is  about  one-fifth  of  the  length  of  the  nail;  is  thin,  soft,  and 
white,  and  is  received  into  a  fold  or  fossa  of  the  true  skin, 
which  is  very  distinct  when  the  cuticle  and  nail  are  removed 
together  by  maceration.  The  concave  surface  of  the  nail 
adheres  closely  to  the  skin  below,  precisely  as  the  cuticle  does 
in  any  other  part  of  the  body,  and  therefore  may  be  loosened 
by  the  same  processes,  as  hot  water  and  maceration.  The 
white  part  of  the  nail,  at  its  root,  is  called  the  crescent,  (lunula,) 
and  is  said,  by  Mosely,*  never  to  exist  in  the  fingers  of  Africans 
or  of  persons  who  have  even  a  slight  mixture  of  negro  blood: 
the  latter  opinion  I  am  disposed  to  consider  incorrect.  This 
appearance,  however,  does  not  depend  upon  any  peculiar  or- 
ganization of  the  nai!  itself  at  that  part,  but  upon  the  cutis  venv 
belpw  it,  which  being  more  vascular  elsewhere,  causes  tLat 
spot  to  Ipok  white,  the  nail  being  semi-diaphanous  and  permit* 

*  Diseases  of 'Warm  Climates. 


THE  NAILS.  343 

ting  a  view  of  the  circulation  beneath.  This  is  also  sufficiently 
proved  by  the  fact,  that  when  a  nail  is  torn  off,  its  lunula  disap- 
pears. The  nail  increases  gradually  in  thickness  from  its  root 
to  its  free  extremity. 

The  nail  is  covered  on  the  posterior  face  of  its  root  by  the 
epidermis,  which  terminates  there  in  a  thin,  adherent,  diapha- 
nous band:  behind  this  band  the  root  of  the  nail  projects,  and 
is  received  into  the  groove  of  the  cutis  vera.  The  epidermis 
also  adheres  to  the  lateral  margin  of  the  nail,  and  in  a  curved 
line  to  the  concave  side  of  its  anterior  end.  The  under  sur- 
face of  the  nail  is  soft,  pulpy,  and  has  an  arrangement  of 
superficial  longitudinal  grooves,  receiving  the  papilla  of  the 
corresponding  surface  of  the  cutis  vera.  As  the  black  co- 
lour of  the  negroes  is  sometimes  seen  beneath  their  nails,  it  is 
probable,  as  stated,  that  the  rete  mucosum  exists  there  also; 
but  it  is  not  so  clearly  ascertained,  though  the  observations  of 
M.  Gaultier,  on  the  rete  mucosum  of  animals,  tend  to  prove 
it.* 

As  the  nails  are  entirely  destitute  of  organization,  having 
neither  vessels  nor  nerves,  they  have  no  power  of  growth  nor 
of  disease  in  themselves,  these  qualities  being  derived  exclu- 
sively from  the  cutis  vera.  The  materials  of  their  formation 
are,  accordingly,  secreted  from  the  cutis  vera,  in  the  bottom  of 
the  groove,  formed  by  the  latter  for  the  reception  of  their  root. 
As  these  materials  adhere  to  the  preceding  formation,  and 
become  concrete,  by  adding  continually  to  its  length,  they 
shove  it  forward,  and  thereby  elongate  it.  While  this  is  going 
on  in  the  groove,  the  thickness  of  the  nail  is  also  somewhat  in- 
creased by  an  excretion  from  the  skin  contiguous  to  its  con- 
cave surface.  This  accounts  for  the  nail  being  thicker  at  its 
free  extremity  than  at  its  root. 

Owing  to  a  peculiarly  morbid  state  of  this  proximate  surface 
of  the  true  skin,  it  sometimes  happens,  that  the  contribution  to 
the  nail  from  it  exceeds  that  from  the  groove;  the  consequence 
of  which  is,  that  the  whole  nail  grows  upwards  like  a  horn,  in- 
stead of  forwards.  An  example  of  this  kind  was  lately  exhi- 
bited to  me  by  a  scientific  friend,  Dr.  Charles  D.  Meigs,  of 
tliis  city,,  in  a  female  aged  about  ninety.  In  this  case  one  of 

*  See  Rete  Mucosum.. 


344  INTEGUMENTS. 

the  big  toe  nails  had  grown  upwards,  in  a  semi-spiral  manner, 
to  the  length  of  four  and  a  quarter  inches,  when  measured 
along  the  outer  edge  of  the  spiral.  The  corresponding  nail 
of  the  other  side  would  have  been  of  nearly  the  same  length, 
but  it  had  been  broken.  The  nails  of  all  the  other  toes 
had  assumed  a  similar  manner  of  growth,  and  measured 
from  one  and  a  half  to  two  inches.  In  the  case  of  each 
nail  its  anterior  extremity  presented  the  primitive  nail  as 
it  had  been  before  this  extraordinary  hypertrophy. 

The  statement  of  the  patient  was,  that  the  growth  had  com- 
menced about  fifteen  years  previously.  A  tendency  to  this 
horny  growth  from  the  skin,  was  also  manifested  in  a  tubercle, 
three  or  four  lines  long,  and  with  an  ulcerated  base,  from  the 
back  of  her  nose;  and  also  by  scaly  excrescences  on  the  legs. 
The  patient  having  died  shortly  afterwards,  the  collection  of 
nails  was  politely  presented  to  the  Anatomical  Museum,  by  Dr. 
Meigs. 

In  cases  where  the  nail  has  been  lost  by  violence  or  disease, 
the  cutis  vera  secretes  another;  but  it  differs  from  the  first,  un- 
less the  cutis  vera  has  been  restored  to  a  perfectly  healthy  ac- 
tion: from  this  cause,  we  see  in  individuals  thick  black  nails, 
sometimes  cleft  longitudinally. 

The  nails  begin  to  appear  about  the  fifth  month  of  fetal  life, 
and  are  still  imperfect  at  birth.  When  analyzed,  they  seem  to 
consist  in  coagulated  albumen,  with  a  small  quantity  of  the 
phosphate  of  lime. 


CHAPTER  IV. 

OF  THE  HAIRS. 

THE  Hairs  (Pili,  Crines)  are  cylindrical  filaments,  which 
are  found  on  most  parts  of  the  skin,  excepting  the  palms  and 
the  soles.  The  finest  of  them  are  microscopical,  and  have  not 
a  diameter  exceeding  the  one-sixth  hundredth  of  an  inch. 


THE  HAIRS.  345 

The  hairs  differ  much  in  their  size  and  appearance  in  the  se- 
veral parts  of  the  body.  Those  on  the  head  (capilli,  caesaries,) 
grow  to  the  greatest  length  of  any,  and  are  most  numerous  in 
proportion  to  the  space  they  occupy.  Those  which  surround 
the  month,  and  are  on  the  cheeks,  (julus,  mystax,  barba,)  ex- 
ceed the  others  in  size,  and  when  allowed  to  grow,  are  next  in 
length,  and  more  disposed  to  curl.  Those  around  the  eyes 
(cilia  and  the  supercilia,)  are  not  disposed  to  exceed  an  inch  in 
length,  and  have  a  long  slender  spindle  shape.  Those  at  the 
orifices  of  the  nostrils  and  ears  are  of  the  same  habits  as  the 
latter.  Those  of  the  arm  pit,  (glandebalae,)  and  about  the  or- 
gans of  generation,  (pubes,)  are  limited  to  the  growth  of  a  few 
inches. 

In  the  male  subject  there  are  hairs  of  considerable  length, 
also,  on  the  sternum,  and  about  the  nipples,  an  arrangement 
which  seldom  occurs  in  females.  In  most  individuals,  hairs 
are  found  over  the  whole  remaining  surface  of  the  body;  but 
in  females,  and  in  many  males,  they  are  too  fine  to  be  readily 
visible.  In  some  subjects,  brought  into  our  dissecting-rooms, 
the  pilous  system  has  been  so  developed  as  to  form  a  shaggy 
coat  over  the  whole  body,  and  almost  to  conceal  the  skin. 

We  are  informed,  on  the  authority  of  Jameson's  Tour,  of 
a  man,  at  Ava,  covered  from  head  to  foot  with  hair.  That 
on  the  face  and  ears  is  shaggy,  and  about  eight  inches  long; 
on  the  breast  and  shoulders  it  is  from  four  to  five.  He  is  a 
native  of  the  Shan  country,  and  married  a  Burmese  woman, 
by  whom  he  has  two  daughters:  the  youngest  is  covered 
with  hair  like  her  father,  but  the  eldest  resembles  her  mo- 
ther.* 

In  the  female  the  hairs  of  the  head  are  more  abundant,  and 
reach  a  greater  length  than  they  do  in  the  male.  As  a  general 
rule,  the  colour  of  the  hairs  corresponds  with  that  of  the  eyes 
and  of  the  skin,  and  the  darker  they  are,  the  coarser.  Accord- 
ing to  WithofF,  a  quarter  of  an  inch  square  of  skin  has  upon  it 
147  black  hairs,  while  the  same  extent  has  162  hazel,  or  182 
white  ones,  in  other  individuals. 

Each  hair  consists  in  a  bulb  and  in  a  stalk.  The  bulb  is  the 
adherent  extremity,  and  is  whiter,  softer,  and  generally  larger 

*  Littell's  Museum,  No.  69;  p.  412. 


34G  INTEGUMENTS. 

than  any  other  part;  it  is  received  into  a  follicle,  compared  ap- 
propriately by  Malpighi  to  the  vase  containing  a  flower  or  plant, 
and  which  is  deposited  most  commonly  in  the  subcutaneous  cel- 
lular substance,  but  sometimes  in  the  skin  itself.  This  follicle 
is  of  an  oblong  ovoidal  shape;  its  open  orifice  is  continuous 
with  the  surface  of  the  body,  while  its  internal  end  is  closed, 
and  has  some  filaments  passing  from  it  to  the  adjacent  cellular 
substance.  It  is  formed  of  two  membranes;  the  external  is 
white,  strong,  and  continuous  with  the  derm  or  cutis  vera;  the 
second  being  within  the  last,  is  more  soft,  delicate,  and  vascu- 
lar, and  seems  to  be  a  continuation  of  the  rete  mucosum.  From 
the  bottom  of  the  cavity  of  the  follicle,  a  small  conoidal  papilla 
erects  itself  towards  the  orifice.  This  papilla  is  vascular,  and 
from  the  dissections  of  M,  Beclard,  on  the  human  subject,  and 
of  M.  Rudolphi,  on  the  mustachios  of  seals,  is  furnished  with 
nerves.  The  mode  of  approach  of  its  vessels  is  not  yet  settled. 
M.  Gaultier  says  that  the  arteries  pass  from  the  surface  of  the 
skin  into  the  orifice  of  the  follicle,  and  then  descend,  in  a  ser- 
pentine manner,  between  its  two  membranes  to  the  bottom.* 
M.  Bdclard,  on  the  contrary,  considers  them  to  pass  through 
the  bottom  of  the  follicle.  Each  piliferous  follicle  is,  moreover, 
furnished,  within  its  orifice,  with  many  small  sebaceous  follicles 
arranged  round  it. 

The  bulb  of  the  hair  has  in  it  a  conoidal  cavity,  open  at  its 
base,  and  receiving  the  conoidal  papilla  of  the  follicle.f  The 
hair  receives  its  nourishment  from  the  papilla.  The  hair  is 
moreover  attached  to  the  skin  by  the  cuticle ;  for  the  latter 
having  reached  the  orifice  of  the  follicle  is  then  reflected  for 
some  distance  along  the  hair:  this  increases  the  strength  of  the 
attachment  of  the  hair  to  the  skin. 

The  stalk  of  a  hair  has  generally  the  loose  extremity  smaller 
than  any  other  part,  and  frequently  split.  When  examined  with 
a  microscope  the  stalk  appears  to  consist  of  two  substances,  one 
within  the  other.  The  exterior  is  a  diaphanous  sheath  almost 
colourless,  and,  from  having  the  properties  of  the  epidermis, 
may  be  a  continuation  of  it.  The  interior  consists  of  from  five 

•  J.  Cloquet,  Anat.  de  1'Homme,  Pi,  CXVIH.  fig.  II, 

t  Gaultier,  see  Cloquet,  loc,  cit, 


THE  HAIRS.  347 

to  ten  filaments,  parallel  with  one  another,  and  forming  a  tube 
in  the  centre  of  the  fasciculus.  The  tube,  as  well  as  the  inter- 
stices between  the  filaments,  is  filled  with  a  fluid  called  the 
marrow  of  the  hair.  This  substance  corresponds  with  one  of 
the  layers  of  the  rete  mucosum  of  the  skin,  and  contains  the  co- 
louring matter.  The  probability  is,  that  the  whole  hair  is  a 
continuation  of  the  rete  mucosum,  to  which  is  joined  the  enve- 
lope of  the  epidermis.  The  canal  in  the  centre  of  the  hair  is 
said  to  be  unusually  distinct  in  the  hog's  bristle ;  it  is  also  well 
seen  in  the  supercilia :  the  follicle  and  bulb  are  best  studied  in 
the  mustachios  of  the  larger  animals.  According  to  Mr.  Heu- 
singer,*  the  substance  of  the  hair,  when  examined  with  a  mi- 
croscope of  strong  power,  exhibits  an  areolar  appearance. 

Though  the  stalk  of  the  hair  is  destitute  of  blood  vessels  and 
of  nerves,  yet  it  is  probable,  from  the  sudden  changes  of  colour 
that  sometimes  occur  in  it  from  black  to  white,  owing  to  terror 
and  grief,  that  there  is  a  species  of  interstitial  circulation  going 
on.  The  emaciated  and  peculiar  appearance  which  sickness 
gives  to  it,  would  also  tend  to  support  this  opinion.  Strictly- 
speaking,  the  hairs  are  devoid  of  sensibility,  yet,  as  the  bulb  is 
planted  over  a  sensitive  papilla,  they  communicate  certain  sen- 
sations by  being  removed  or  touched.  Animals  apply  their 
mustachios  particularly  to  this  use  in  groping  through  dark 
places,  or  when  they  are  deprived  of  sight.  The  hairs  are  emi- 
nently hygroscopic,  moisture  lengthens,  and  dryness  shortens 
them ;  this  property  has  caused  them  to  be  applied  to  the  con- 
struction of  hygrometers. 

In  certain  animals  the  hairs  are  erected  by  the  contraction 
of  the  subcutaneous  muscle;  the  movement  in  the  human  sub- 
ject corresponding  with  that,  is  the  effect  of  great  fright,  and  is 
produced  by  the  contraction  of  the  occipito  fronta-lis  muscle. 

In  the  development  of  hair,  the  part  which  first  forms  is  the 
follicle,  the  young  hair  then  pierces  it  at  its  summit,  in  the  same 
way  that  the  tooth  pierces  its  capsule.  The  death  of  the  cap- 
sule, or  the  drying  up  of  its  fluids,  occasions  the  fall  of  the  hair 
and  prevents  its  regeneration.  In  old  men  who  are  bald  there 
is  no  appearance  of  capsules;  while  in  persons  from  whom  the 
hair  has  fallen,  owing  to  sickness,  as  the  capsules  still  remain, 

*  J.  Cloquet,  loc.  cit. 


348  INTEGUMENTS. 

they  soon  put  forth  another  crop  of  hair.  The  rudiments  of  the 
hair  are  seen  about  the  fifth  month  of  foetal  life.  The  first  crop 
is  deciduous,  and  after  covering  the  body  of  the  foetus  like  a  fine 
down,  till  the  eighth  month  of  utero-gestation,  it  then  falls  off: 
sometimes,  however,  it  is  retained  either  in  whole  or  in  part 
till  after  birth ;  this  is  particularly  the  case  in  regard  to  the  hair 
of  the  head.  In  this  deciduous  character  we  see  another  analo- 
gy between  the  hair  and  the  teeth. 

When  the  hair  becomes  white  from  age,  the  conversion 
of  colour  begins  at  the  loose  extremity,  another  proof  of  the 
interstitial  circulation,  or  change  of  particles  in  it.  The  same 
fact  is  observable  in  animals  who  change  colour  only  for  the 
winter.  But  the  restoration  of  colour  begins  at  the  root. 

It  is  probable,  in  those  cases  of  plica  polonica  attended  with 
bleeding  from  the  root  of  the  hair  when  it  is  cut,  that  the  vas- 
cular papilla  has  been  so  much  augmented  as  to  elevate  itself 
above  the  level  of  the  cuticle,  and  of  course  interferes  with  the 
sweep  of  the  razor  employed  in  shaving  the  head.  Ignorance 
in  regard  to  the  organization  of  the  hair,  and  a  slight  inclination 
to  the  marvellous,  would  magnify  this  into  every  hair,  in  such 
a  disease,  being  a  sort  of  branch-pipe  from  the  general  circu- 
lating system,  and  therefore  bleeding  upon  being  wounded. 
Many  of  the  victims  to  this  disease  accordingly  prefer  the  loath- 
some matting  of  the  hair  with  which  it  is  accompanied,  to  the 
supposed  risk  of  dying  by  hemorrhage. 


BOOK    III. 


PART    I. 

CHAPTER   I. 

ON  THE  GENERAL  ANATOMY  OF  THE  MUSCLES.* 

THE  muscles  (musculi)  by  their  contraction  produce  the  va- 
rious flexions  of  the  body,  and  are,  therefore,  the  organs  of  mo- 
tion. They  may  be  known  by  their  redness,  softness,  irrita- 
bility, contractility,  and  by  their  being  formed  of  long  parallel 
fibres.  The  redness,  however,  does  not  always  attend  them  ; 
as  this  colour  is  very  faint  in  the  foetus,  and  does  not  exist  at 
all  in  animals  that  have  not  red  blood.  They  form  a  very  con- 
siderable share  of  the  whole  bulk  of  the  body. 

Though  the  most  perfect  organs  of  motion,  and  producing  it 
more  efficiently  and  rapidly  than  any  other  apparatus,  they  are 
not  indispensable  to  it;  for  they  are  not  observable  in  animals  of 
a  very  low  grade,  which  apparently  consist  of  a  sort  of  cellular 
or  mucous  substance.  In  the  next  grade  of  animals,  as  the 
worms,  where  there  is  a  deficiency  both  of  bony  and  of  carti- 
laginous skeleton,  the  muscles  are  perceptible,  and  produce  lo- 
comotion by  their  attachment  to  the  skin  or  integuments;  and, 
finally,  in  animals  which  have  a  skeleton,  the  muscles  are  al- 
most exclusively  attached  to  its  different  points,  and  by  alter- 
nately approximating  them,  effect  locomotion. 

The  muscles  of  the  human  body  are  referrible  to  two  classes, 
in  consequence  of  their  position  and  functions,  though  they  pre- 

*  These  organs  were  very  imperfectly  known  to  the  ar  dents,  excepting  Ga- 
lon, and  had  not  generally  received  names  till  the  time  of  Sylvius,  A.  D.  1587. 
The  paramount  authority  of  Albinus,  in  this  department  of  anatomy,  in  his  work 
Historia  Musculorum  Hominis,  Leydcn,  1734,  has  induced  me  to  adopt  it  as  the 
standard  of  correct  description  and  nomenclature,  with  but  few  exceptions. 

VOL.  I.— 30 


350  MUSCLE?. 

sent  a  perfect  similitude  of  structure  every  where.  The  most 
numerous  class,  as  well  as  that  in  which  they  are  of  the  greatest 
magnitude,  are  the  muscles  of  voluntary  motion :  they  are  placed 
between  the  skeleton  and  the  integuments,  and  constitute  the 
principal  bulk  of  the  extremities,  and  also  afford  a  thick  fleshy 
covering  to  the  trunk.  The  second  class  is  contained  within 
the  large  cavities  of  the  skeleton,  and  forms  a  portion  of  the 
structure  of  the  circulatory,  of  the  digestive,  and  of  the  urinary 
organs ;  and  produces  the  principal  internal  motions  of  the  ani- 
mal economy. 

Every  muscle  is  surrounded  by  an  envelope  of  cellular  sub- 
stance, called  its  sheath,  (Membrana  Musculorum  Communis*) 
which  at  different  points  of  the  body  exhibits  various  degrees  of 
condensation.  In  the  muscles  of  voluntary  motion  these  sheaths 
are  formed  by  partitions,  going  from  the  aponeurotic  expansions 
just  beneath  the  skin,  to  the  periosteum,  and  are  the  prolonga- 
tions which  induced  Bichat  to  consider  the  periosteum,  as  the 
centre  of  the  desmoid  system.  These  sheaths  in  some  cases  pre- 
serve to  a  considerable  extent  the  ligamentous  appearance,  but 
generally  cellular  substance  predominates  in  them.  Upon  their 
existence  is  founded  the  great  variety  of  views  and  descriptions 
which  the  later  anatomists  have  taken  of  the  fascia?  of  the  hu- 
man body,  some  choosing  to  describe  them  in  one  way  and  some 
in  another.  The  sheaths  of  the  second  class  of  muscles  are  com- 
posed of  a  much  finer  and  looser  coat  of  cellular  substance  than 
those  of  the  first,  and  are  commonly  described  as  lamina?  or  tu- 
nics to  the  organs  to  which  they  respectively  belong.  In  every 
ease,  however,  from  the  internal  face  of  these  sheaths  a  great 
many  partitions  pass  off,  which  penetrate  the  body  or  thickness 
of  the  muscle,  and  divide  and  subdivide  it  into  fasciculi,  and  into 
fibres,  even  to  their  most  minute  condition.  These  partitions  be- 
come thinner  the  more  they  are  multiplied. 

Many  of  the  muscles  are  subdivided  by  fissures,  into  several 
large  portions  called  Fasciculi,  or  Lacerti.  These  vary  very 
much  in  size,  and  in  their  distinctness  from  each  other.  Some 
are  so  large  and  so  widely  separated  as  to  appear  like  distinct 
muscles;  such,  for  example,  are  the  biceps  of  the  arm  and  of  the 
thigh,  the  deltoid,  the  columnar  carneas  of  the  heart,  and  several 
others.  But  the  greater  part  of  the  fasciculi  are  strictly  parallel 

*  Haller,  Element.  Physiol.  torn.  i. 


GENERAL  ANATOMY  OF  THE  MUSCLES.  351 

with  each  other,  and  merely  separated  by  a  thin  lamina  of  eel* 
lular  substance.  The  fasciculi  are  again  subdivisible  into  fibres, 
which  from  their  smallness  are  not  appreciable  to  the  naked 
eye,  and  even  when  examined  with  powerful  microscopes  seem 
to  admit  of  an  endless  division.  On  this  account  some  anato- 
mists have  undertaken  to  classify  the  fasciculi  under  the  terms 
of  first,  second,  and  third  orders.  It  is  evident,  however,  thai 
this  arrangement  is  too  arbitrary  to  be  needful,  and  that  the 
circumstance  is  sufficiently  expressed  by  considering  the  fasci- 
culi as  indefinitely  divisable.  The  fibrous  arrangement  of 
muscles  is  rendered  still  more  distinct  by  boiling  them,  or  by 
immersing  them  in  alcohol. 

The  structure  of  the  muscular  fibre  has  been  studied  with 
great  attention  by  microscopical  observers.  From  such  ob- 
servations, it  appears  that  their  ultimate  shape  is  prismatic, 
pentagonal,  or  hexagonal.  According  to  Prochaska,  every 
fibre  extends  the  whole  length  of  the  muscle,  considering  this 
length  as  represented  by  the  tendinous  beginning  on  the  one 
hand,  and  the  tendinous  termination  on  the  other.  This  ar- 
rangement holds  even  in  regard  to  the  longest  muscles,  as  the 
sartorius^ 

The  most  approved  accounts,  of  modern  times,  of  the  ulti- 
mate structure  of  muscular  fibre,  are  those  of  Mr.  Bauer;  with 
Sir  Everard  Home,  and  of  MM.  Prevost  and  Dumas.  These 
gentlemen  concur  in  stating  that  the  results  have  been  uniform 
in  all  animals  to  which  their  observations  have  been  extended. 
That  the  muscular  fibre  is  a  series  of  globules,  resembling  the 
globules  of  the  blood  deprived  of  colouring  matter  and  adhering 
in  a  line  to  each  other.  That  the  medium  of  adhesion  is  invi- 
sible from  its  transparency  and  want  of  colour;  but  if  the  mus- 
cle be  macerated  in  water  frequently  changed,  that  this  medium, 
from  its  greater  solubility  and  more  ready  putrefaction,  may  be 
removed  so  as  to  leave  the  globules  detached  from  each  other, 
and  still  resembling  the  globules  of  the  blood.  The  fact  of  the 
globular  condition  of  the  muscular  fibre  was  first  pointed  out 
by  Leuwenhoek  and  Hook ;  it  is  also  confirmed  by  the  testi- 
mony of  Mr.  Milne  Edwards  and  M.  Dutrochet.  The  evidence 
of  their  size  is  very  unsettled ;  it  is  stated  at  from  one  diameter 
to  one-seventh  of  the  diameter  of  a  globule  of  blood,  the  latter 


352  MUSCLES* 

being  estimated  at  the  two-thousanth  part,  or  less,  of  an  inch* 
Such  minute  observations  are  necessarily  very  uncertain. 

In  meat  which  is  prepared  for  the  table  by  roasting  or  boil- 
ing, or  in  a  muscle  which  is  contracted,  one  frequently  sees 
the  fibres  undulated  or  crooked.  By  Prochaska  it  is  attributed 
to  the  bridling  of  the  fibre,  by  the  contraction  of  its  cellular 
substance,  nerves,  and  blood  vessels.  The  cause,  however,  i» 
not  well  ascertained :  the  condition  seems  to  be  one  of  the  pe- 
culiarities of  muscular  fibre,  which  it  manifests  when  in  a  state 
of  contraction  only;  for  it  disappears  whenever  the  fibre  is  re- 
laxed, either  by  spontaneous  movement,  or  by  stretching  it  in 
the  dead  body.  This  undulation  has  probably  contributed  to 
the  many  inexact  observations  on  the  structure  of  muscles. 
Thus,  Haller  thought  they  consisted  in  a  series  of  ovoid  vesi- 
cles, which  lengthened  in  a  state  of  relaxation,  and  became 
more  globular  in  a  state  of  contraction.  It  is  unnecessary  to 
dwell  on  mere  errors  of  the  eyes  or  of  the  imagination,  for  the 
fact  seems  to  be  now  well  established,  that,  though  the  muscu- 
lar fibre,  by  contracting,  loses  its  straightness  and  becomes 
crooked,  yet  this  is  effected  without  change  in  the  form  of  the 
ultimate  globules  of  which  it  consists. 

By  some  it  has  been  asserted  that  muscles  are  only  the  con- 
tinuation of  blood  vessels.  To  this  it  is  replied,*  that  though 
insects  have  muscles,  yet  they  have  not  blood  vessels,  so  that 
the  former  cannot  be  a  continuation  of  the  latter.  Moreover, 
a  successful  injection,  though  it  may  penetrate  very  finely  be- 
tween the  fibres,  so  as  to  cause  the  muscle  to  swell  considera- 
bly, yet  none  of  these  vessels  can  be  traced  into  the  ultimate 
fibre.  The  vital  phenomena  and  the  organization  of  muscular 
fibre,  are  so  very  different  from  cellular  substance,  from  nerves, 
and  from  vessels,  that  it  cannot  be  less  than  a  distinct  struc- 
ture. 

Notwithstanding  this  limitation,  which  is  put  upon  the  dis- 
tribution of  the  blood  vessels,  every  muscle  is  abundantly  sup- 
plied by  them.  The  arteries  come  from  the  adjacent  large 
trunks,  and  penetrate  at  different  points  of  the  periphery  of  the 
muscle.  They  first  of  all  pass  between  the  larger  fasciculi  and 

*  Beclard,  Anat.  Gen. 


GENERAL  ANATOMY  OF  THE  MUSCLES.  353 

parallel  with  them;  they  then  divide  and  follow  the  course  of 
the  smaller  fasciculi;  they  divide  and  subdivide  again  after  the 
same  rule,  till  they  become  mere  capillary  tubes,  from  which 
the  nutritive  matter  is  exhaled.  The  veins  accompany  the 
arteries,  and  receive  their  blood;  some  of  them  creep  along  the 
surface  of  the  muscle  without  having  corresponding  arteries. 
Bichat  says  that  they  are  injected  with  great  facility  from  their 
trunks,  from  which  he  supposes  that  their  valves  are  less  nu- 
merous than  in  other  parts  of  the  system. 

The  colour  of  the  muscular  fibre  seems  to  be,  in  a  measure, 
independent  of  the  blood  which  circulates  in  it.  Some  animals 
with  red  blood  have  white  fibres,  as  frogs.  The  colour  of  the 
muscular  fibre  is  not  altered  in  animals  that  have  been  suffo- 
cated. The  muscular  fibres  of  the  intestines  and  of  the  bladder, 
though  abounding  in  blood  vessels,  are  whiter  than  the  muscles 
of  voluntary  motion. 

Lymphatics  have  been  injected  in  the  intervals  between  mus- 
cles and  between  their  fasciculi. 

The  Nerves  of  the  muscles  are  large  and  abundant,  as  the 
nerves  of  the  brain  and  spinal  marrow  are  chiefly  spent  upon 
them.  They  are  generally  proportioned  to  the  size  of  the  mus- 
cle which  they  have  to  supply,  but  there  is  some  variety  in  this 
respect.  They  accompany  the  arteries,  and  are  united  to  them 
by  cellular  substance.  Their  ultimate  terminations  are  traced 
with  great  difficulty,  and  there  is  consequently  an  uncertainty 
in  this  respect.  Before  they  disappear  they  become  soft  by 
divesting  themselves  of  their  cellular  envel  >pe,  and  are  supposed 
to  bring  thus  their  medullary  substance  in  immediate  contact 
with  the  muscular  fibre.  The  recent  observations  of  MM.  Pre- 
vost  and  Dumas,  are  thought  to  throw  some  light  on  this  sub- 
ject, and  have  been  received  with  a  very  respectful  attention. 
They  say,  that  by  macerating  in  clean  water,  and  in  a  dark 
place,  the  muscle  of  a  bullock,  and  then  throwing  a  strong  con- 
centrated light  upon  it,  the  distinction  of  colour  between  the 
nerves  and  the  muscular  fibres  becomes  very  apparent.  With 
the  aid  of  a  microscope  and  a  fine  knife,  the  nervous  ramifica- 
tions may  be  thus  traced.  The  trunk  of  the  nerve  enters  the 
muscle  parallel  with  its  fibres,  and  soon  begins  to  give  off,  at 

30* 


354  MUSCLES. 

right  angles,  lateral  filaments,  which  penetrate  between  the  fas- 
ciculi and  fibres  of  the  muscles,  and  may  be  traced  to  the  top 
of  the  undulations  formed  in  the  muscular  fibres.  These  lateral 
filaments  at  some  places  are  two  in  number,  which  pass  at  some 
distance  from  each  other,  but  parallel,  and  terminate  by  an 
interchange  of  fikments;  at  other  places  the  terminating 
branches  are  spread  out  transversely  to  the  muscular  fibre, 
and  end  by  forming  loops  with  themselves.  According  to  this 
view,  the  nervous  filaments,  strictly  speaking,  have  no  termi- 
nation,  but  run  again  into  the  source  from  which  they  are  de- 
rived. 

The  chemical  analysis  of  muscles  shows  them  to  be  com- 
posed of  fibrine,  albumen,  gelatine,  extractive  matter,  the  phos- 
phate of  sodst,  ammonia,  and  of  lime,  and  of  the  carbonate  of 
lime.  The  extractive  matter  of  the  muscle  may  be  removed 
by  maceration  in  clean  water,  often  changed.  If  it  be  allowed 
to  remain  long,  it  assumes  certain  appearances  in  its  putre- 
faction peculiar  to  itself,  but  occasionally  it  is  converted  into  a 
substance  resembling  spermaceti.  When*  a  muscle  is  exposed 
to  boiling  water,  the  albumen  is  raised  to  the  surface,  like 
foam;  the  gelatine  coagulates  when  the  muscle  is  cold;  and  the 
fibrine  appears  as  a  fibrous  grayish  substance,  insoluble  in  hot 
water,  closely  resembling  the  irbrine  of  the  blood,  and  evolv- 
ing large  quantities  of  nitrogen  by  the  action  of  nitric  acid. 
When  a  muscle  is  exposed  to  the  fire  alone,  as  in  roasting, 
the  albumen  is  hardened;  the  gelatine  is  melted,  and  runs  oflf, 
in  part,  with  the  juices  of  the  meat:  the  extractive  matter  is 
that  which  gives  a  dark  colour  to  the  outside;  the  fibrine  is 
cooked  in  the  juices  of  the  meat,  and  is  then  rendered  very 
tender.  The  muscular  parts  of  animals  are  amongst  the  easiest 
of  digestion. 

The  muscular  system  of  the  embryo  is  first  of  all  in  a 
gelatinous  state,  and  confounded  with  cellular  substance^ 
but  at  two  months  from  conception,  the  fibres  are  distinct, 
and  at  four  they  begin  to  contract  and  to  execute  different  mo- 
tions. 

The  muscular  system  is  subject  to  varieties  of  conformation. 

Hobust,  muscular  individuals  frequently  have  supernumerary 

.  muscles  and  supernumerary  heads  to  their  muscles,  particularly 


MUSCULAR  MOTION.  355 

in  the  extremities.  In  monstrous  foetuses  it  sometimes  hap- 
pens that  the  muscular  system  is  either  wholly  or  partially 
supplanted  by  adipose  matter  and  by  infiltrated  cellular  sub- 
stance. 


CHAPTER  II. 

ON  MUSCULAR  MOTION. 

THE  muscles,  after  death,  are  soft,  easy  to  tear,  and  have 
but  little  elasticity;  it  is  only  during  life  that  they  manifest  such 
extraordinary  strength,  and  retain  their  powers  of  motion. 
The  general  phenomena  of  the  latter  have  been  happily  ex- 
pressed by  the  word  myotility,  suggested  by  M.  Chaussier. 
These  phenomena  are,  contraction,  elongation,  and,  according 
to  Barthez,  a  power  of  remaining  motionless  or  fixed. 

In  contracting,  the  muscle  shortens,  swells  and  becomes 
hard;  presents  wrinkles  on  its  surface;  and  its  fibres  are  some- 
times thrown  into  a  state  of  oscillation  or  vibration,  from  their 
alternate  relaxation  and  contraction.  It  is  owing  to  the  vibra- 
tory motion  in  the  fibres  of  a  muscle,  during  their  contraction, 
that  a  rustling  is  heard  on  the  application  of  the  stethoscope  to 
them.  The  hollow,  distant  rumbling,  when  the  meatus  exter- 
nus  is  closed  by  the  finger,  is  owing  to  the  same  vibration  in 
the  muscles  of  the  finger  employed.  This  is  readily  proved  by 
the  following  experiment:  close  the  meatus  with  the  end  of  the 
handle  of  an  awl  or  a  fork,  pressed  against  it  by  the  finger,  and 
it  will  be  found  that  the  muscular  vibrations  are  continued 
along  the  instrument:  plant,  afterwards,  the  point  of  the  instru- 
ment upon  a  soft,  inelastic  substance,  so  as  to  make,  in  that 
way,  the  closure  of  the  meatus,  and  the  rumbling  will  instantly 
cease.  The  roaring  noise  of  sea-shells  may  be  explained  In 
the  same  way.  The  colour  remains  the  same,  which  proves 
that  there  is  not  an  appreciable  addition  to  the  quantity  of  its 
circulating  fluids.  The  rapidity  with  which  this  contraction 
may  take  place,  is  manifested  in  speaking,  in  running,  and  in 
playing  upon  a  stringed  instrument;  and  its  strength,  by  the 
immense  burdens  that  some  individuals  can  raise  and  bear, 


356  MUSCLES. 

The  power  of  elongation  or  relaxation  seems  to  be  an  active 
state  of  the  muscle,  as  well  as  its  contraction.  This  power  of 
relaxation  or  of  elongation  is  much  inferior  to  that  of  contrac- 
tion; it  seems  to  be  only  what  is  sufficient  to  restore  the  mus- 
cle to  its  proper  length,  so  as  to  put  it  in  a  condition  for  the 
renewal  of  its  contractions.  The  fixedness  of  muscles,  which 
are  contracted  spasmodically,  and  their  retaining  this  position 
even  after  death,  until  putrefaction  begins  to  assail  them,  show 
that  the  power  of  elongation  does  not  depend  simply  upon 
elasticity;  for  the  latter  quality  being  as  much  the  attribute  of 
dead  as  of  living  matter,  would  be  brought  into  play  on  death. 

The  fixation  of  muscles  is  not  a  distinct  power,  but  merely 
a  qualification  of  contraction,  by  which  the  latter  may  be  ar- 
rested at  any  given  point,  and  retained  there. 

As  every  muscle  augments  in  thickness  during  its  contrac- 
tion, it  has  been  a  subject  of  inquiry  to  physiologists  whether 
the  whole  mass  of  muscle  was  increased  or  diminished  by  its 
contraction.  Swammerdam,  in  order  to  ascertain  it,  put  an 
insulated  solid  muscle,  not  yet  dead,  into  a  tube  filled  with  wa- 
ter; by  irritating  the  muscle,  and  causing  it  to  contract,  the 
water  descended;  but  this  result  was  not  uniform.  When  an 
arm  is  plunged  into  a  tube  properly  formed  and  filled  with  wa- 
ter, if  the  muscles  be  caused  to  contract,  the  fluid  descends; 
but  the  objection  to  the  inference  from  this  experiment  is,  that 
when  all  the  muscles  of  the  arm  are  caused  to  contract  vio- 
lently, the  introduction  of  arterial  blood  is  much  arrested,  if 
not  fully  stopped;  and  the  venous  blood  is  at  the  same  time  ex- 
pelled :  so  that  the  change  in  the  size  of  the  member  may  be 
accounted  for  in  that  way.  The  experiments  of  Erman  on  eels, 
fully  immersed  in  a  fluid,  and  submitted  to  Galvanic  influence, 
are  said  to  substantiate  the  theory  cf  the  muscles  diminishing 
in  bulk  by  contracting.* 

The  activity  of  a  muscle,  though  closely  depending  upon  the 
•afflux  of  blood  to  it,  is  not  entirely  so;  for  it  is  ascertained  that 
Galvanism  will  cause  the  muscles  of  frogs  to  contract,  when 
the  circulation  is  arrested  by  death,  or  when  the  blood  is  co- 
agulated, or  even  when  it  has  been  drawn  off.t  This  pheno- 

*  Beclard;  loe.  cit. 

t  Prochasku  dc  Carne  Muscular!.     Vienne,  1778. 


MUSCULAR  MOTION.  357 

menon,  however,  can  only  last  a  comparatively  short  time; 
for  a  muscle  soon  dies,  and  runs  into  a  state  of  mortification, 
after  its  vascular  and  nervous  communications  have  been  cut 
off.  Physiologists  have  entertained  very  different  opinions  on 
the  causes  of  the  muscles  contracting,  or  on  muscular  irritabi- 
lity, as  it  is  called.  Some  have  supposed  it  to  be  an  attribute 
of  the  muscle  itself;*  others,  that  it  depended  on  the  blood  ves- 
sels, which,  by  bringing  a  greater  afflux  of  fluids  into  its  inte- 
rior, between  its  fasciculi  and  fibres,  obliged  the  two  latter  to 
take  a  more  flexuous  course;  and  others,  on  the  nerves.f  Any 
decision  on  this  point  is  inconclusive,  because  it  is  well  known 
that  perfect  muscular  action  requires  a  healthy  state  of  the 
muscle,  and  an  uninterrupted  nervous  and  sanguineous  influence; 
so  that  it  seems  to  be  a  result  from  the  combination  of  three 
systems,  more  than  an  attribute  of  one  alone.f 

MM.  Dumas  and  Prevost  say,  that  in  consequence  of  the  final 
nervous  ramifications  crossing  the  muscular  fibres  at  right  an- 
gles to  them,  and  parallel  with  one  another,  the  Galvanic  current 
which  passes  through  these  ramifications,  causes  the  latter  to 
approach  each  other  reciprocally;  whereby  the  muscular  fibres 
to  which  the  ramifications  are  fixed,  are  thrown  into  wrinkles. 
It  is  clear,  from  this  theory,  that  the  muscular  fibres  themselves 
are  destitute  of  the  power  of  contraction,  and  that  they  are  only 
the  frame-work  upon  which  the  Galvanic  batteries  of  the  ner- 
vous system  are  displayed. 

There  are  no  muscles  which  have  not  the  power  of  contract- 
ing some  time  after  apparent  death,  and  this  phenomenon  fre- 
quently continues  for  an  hour;§  it  is  uncommon  for  it  to  cease 
with  the  apparent  extinction  of  life.  This  irritability  is  of  dif- 
ferent durations  in  the  different  muscles;  it  is  first  lost  in  the 
left  ventricle  of  the  heart;  then  in  the  large  intestines;  after- 
wards in  the  small,  and  in  the  stomach;  and  then  in  the  blad- 
der; then  in  the  right  ventricle,  the  iris,  and  in  the  voluntary 
muscles,  of  which  those  of  the  trunk  die  first;  those  of  the  in- 

*  Haller,  Physio!. 

t  Legallois  sur  le  principe  de  la  vie. 

t  Meckcl,  Anat.  Gen.;  from  Barzellotti,  Esame  di  alcuni  moderne  teorie  inter- 
no  alia  causa  prossima  della  contrazione  moscolare,  1796. 

§  The  recent  visitation  of  cholera  in  Europe  and  in  this  country  has  given  many 
persons  an  opportunity  of  examining  this  singular  fact. 


358  MUSCLES. 

ferior  extremities  next,  and  those  of  the  superior  last.  The  last 
act  of  life  is  in  the  auricles,  of  which  the  right  pulsates  longest. 
Different  circumstances  may  produce  some  variety  of  this  pro- 
gress, in  the  loss  of  muscular  irritability,  but  it  will  be  found  ge- 
nerally correct.*  The  experiments  of  Himlyf  demonstrate, 
that  laurel  water,  or  that  of  bitter  almonds,  applied  to  the  sto- 
mach or  brain,  renders  the  heart  insensible  to  the  strongest  sti- 
mulants, while  the  muscles  of  volition  continue  to  move  for 
some  hours  afterwards.  The  duration  of  irritability  is,  however, 
much  varied,  according  to  the  nature  of  the  death,  and  the  state 
of  health  preceding.  Nysten  asserts,  that  he  has  seen  the  right 
auricle  of  a  robust  man  pulsate  nine  hours  after  death.  In  death 
from  chronic  diseases,  with  much  emaciation,  the  heart  ceases 
to  beat  shortly  after  intellectual  phenomena  cease.  And  in 
death  from  electricity;  from  a  blow  upon  the  stomach;  from  the 
inhalation  of  carburetted  hydrogen  gas,  and  some  other  poison- 
ous ones,  muscular  contraction  ceases  universally  in  a  few  mo- 
ments, and  cannot  be  excited  by  any  artificial  means. 

The  irritability  of  the  muscles  is  so  modified  that  certain  sti- 
mulants are  peculiarly  appropriate  to  one  and  not  to  another. 
For  example,  light  is  the  specific  stimulant  to  the  iris;  a  me- 
chanical application,  to  it  as  in  making  artificial  pupil,  is  borne 
frequently  without  its  contracting.  The  heart  is  very  sensible 
to  mechanical  stimulants,  and  additionally  so  when  they  are 
applied  to  its  internal  surface. 

Some  of  the  muscles  are  regularly  under  the  influence  of  the 
will,  others  not  at  all  so,  which  has  given  rise  to  their  division 
into  voluntary  and  involuntary.  These  states,  though  kept  per- 
fectly distinct  from  each  other  in  health,  are  sometimes  blend- 
ed in  disease,  the  voluntary  muscles  becoming  involuntary  in 
their  actions,  and  the  involuntary  voluntary;  which,  however, 
is  much  more  uncommon  than  the  other. 

The  voluntary  muscles  are  generally  such  as  serve  for  loco- 
motion and  speech,  and  receive  their  nerves  directly  from  the 
spinal  marrow.  The  involuntary  muscles  are  such  as  are  con- 
cerned in  the  functions  of  digestion,  respiration,  and  circulation, 
and  which,  in  order  to  continue  the  life  of  the  animal,  must 

*  Meckel,  Anat.  Gen. 

|  Commentatio  <Je  Morte,  Goettingue,  1794. 


MUSCULAR  MOTION.  359 

never  cease  their  actions  for  any  long  interval.  It  is  worthy  of 
remark,  that  apoplexy  and  other  cerebral  affections,  paralyze, 
most  commonly,  the  voluntary  muscles  alone,  while  the  others 
retain  their  usual  state  and  sensibilities. 

When  irritability  is  entirely  gone  from  a  muscle,  and  it  is 
actually  dead,  the  whole  muscular  system  becomes  stiff,  begin- 
ning with  the  trunk,  then  the  inferior,  and,  lastly,  the  superior 
extremities.  This  stiffness  seems  to  be  independent  of  the  ner- 
vous system,  as  the  destruction  of  the  spinal  marrow,  the  cut- 
ting of  nerves,  and  hemiplegia  do  not  arrest  it.  It  is  thought, 
by  M.  Beclard,  to  be  analogous  to  the  contraction  of  the  fibrine 
of  the  blood;  and,  like  the  latter,  does  not  cease  till  putrefac- 
tion begins.  The  degree,  as  well  as  the  time,  of  its  access  is 
variable  under  different  circumstances.  In  very  aged  persons; 
in  such  as  have  died  from  protracted  disease  attended  with 
great  emaciation ;  in  scorbutic  and  gangrenous  diseases,  the 
stiffness  comes  on  quickly,  is  very  slight,  and  disappears  in  a 
couple  of  hours.  But  in  muscular  subjects  who  have  died  from 
sudden  violence  or  from  acute  diseases,  the  stiffness  is  some- 
times postponed  for  twelve  hours  or  more,  and  may  continue, 
in  the  winter,  from  three  or  four  days  to  a  week,  or  even 
longer,  depending  upon  the  access  of  putrefaction. 

The  sensibility  of  the  muscles  is  moderate.  When  they  have 
been  much  exercised,  they  only  give  out  the  sensation  of  fa- 
tigue. In  amputations,  the  pain  of  cutting  through  them  is  not 
equal  to  that  of  the  skin.  In  inflammations  they,  as  most  other 
parts,  have  their  sensibility  exalted  to  an  exquisite  degree. 


CHAPTER  III. 

OF  THE  MECHANICAL  SHAPE  AND  ARRANGEMENT  OF  THE 
VOLUNTARY  MUSCLES. 

EVERY  muscle  consists  in  a  belly  and  in  two  extremities,  of 
which  the  one  that  is  the  fixed  point  is  the  head  or  origin,  and 
the  other  is  the  tail  or  insertion.  The  belly  or  body  is  the 
fleshy  part,  the  extremities  are  generally  tendinous,  either  com- 
pletely or  partially. 


860  MUSCLES. 

Some  of  the  muscles  arise  by  a  single  head,  and  are  inserted 
into  one  point.  Some  few  arise  by  a  plurality  of  heads,  but 
have  a  single  insertion,  as  the  biceps  flexor  of  the  arm,  and  of 
the  thigh;  others,  again,  have  a  single  head,  but  a  plural  inser* 
tion,  as  the  flexors  of  the  fingers  and  of  the  toes;  others,  again, 
have  multiplicate  heads  and  multiplicate  insertions,  as  the  mus- 
cles of  the  back. 

The  most  simple  muscles  are  such  as  have  their  fibres  run- 
ning in  the  direction  of  the  length  of  the  muscles,  of  which 
there  are  many  examples,  as  the  sartorius,  the  biceps  flexor 
cubiti,  the  semi-tendinosus,  and  others.  Others,  again,  have 
their  fibres  running  obliquely  from  a  tendon  or  a  bony  origin 
on  one  side  of  the  muscle,  to  a  tendon  on  the  other,  as  the  se- 
mi-membranosus,  the  peronei,  &c.;  these  are  called  musculi 
semi-pennati.  Others  have  a  long  tendon  in  the  centre,  to 
which  the  fibres  converge  obliquely,  forming  an  angle  with 
each  other;  they  are  the  penniform,  (musculi  pennati.)  Others, 
again,  are  formed  of  a  congeries  of  smaller  muscles,  the  fibras 
of  which  run  in  different  directions  and  are  intermixed  with 
tendinous  matter,  as  the  deltoid  and  the  subscapular.  As  the 
strength  of  a  muscle  depends  upon  the  number  of  its  fibres, 
those  whose  fibres  go  obliquely  are  stronger  than  if  their  fibres 
had  run  longitudinally. 


CHAPTER  IV. 

OF  THE  TENDONS,  (TENDINES.) 

THE  tendinous  extremities  of  muscles,  present  themselves 
under  two  general  shapes:  one  is  funicular,  or  like  cords,  va- 
rying in  shape  from  cylindrical  to  paraboloid;  the  other  is 
spread  out  into  a  membrane,  and  resembles  an  aponeurosis. 
They  both  adhere  with  great  tenacity  to  the  muscular  fibres, 
so  as  to  have  induced,  erroneously,  the  opinion  of  absolute  con- 
tinuity: but  maceration  and  boiling  will  separate  them,  and  the 
course  of  the  fibres  is  different  even  to  the  naked  eye;  besides 
the  very  obvious  difference  in  colour,  in  consistence,  and  in 
vital  properties. 


THE  TENDONS.  361 

The  tendons  are  surrounded  by  a  loose  cellular  membrane  or 
capsule,  which  permits  them  to  glide  freely  upon  each  other : 
in  some  places  this  membrane  is  wanting,  and  is  supplied  by  a 
synovial  membrane  answering  the  same  purposes. 

The  tendons  are  readily  recognised  by  their  white  and  shining 
appearance;  they  have  no  elasticity  or  power  of  elongation 
and  contraction,  and,  therefore,  like  other  ligamentous  matter, 
they  are  lacerated  sooner  than  they  can  be  stretched.  They 
are  composed  of  desmoid  tissue,  the  fibres  of  which  are  united 
by  a  compact  cellular  substance  in  small  quantities.  The 
fibres  are  longitudinal,  and  may  be  readily  separated  either  by 
maceration  or  by  a  slight  boiling.  When  a  round  tendon  is 
prepared  in  this  way,  it  is  easy  to  flatten  it  out  into  an  aponeu- 
rotic  membrane :  the  fibres  are  then  made  very  distinct,  and 
seem  to  adhere  to  each  other  by  lateral  fibrillae.  In  ordinary 
health  no  red  blood  penetrates  into  the  tendons,  but  if  they  be- 
come inflamed,  as  their  capillaries  then  enlarge,  they  admit  the 
red  globules;  at  the  same  time  their  sensibility,  from  being  en- 
tirely organic,  or  what  is  only  sufficient  for  the  internal  actions 
of  the  organ,  is  so  much  augmented  as  to  be  very  manifest.* 
No  nerves  have  been  traced  into  them.  The  tendons  have  the 
character,  at  large,  of  the  desmoid  tissue,  but  are  more  gela- 
tinous, or  completely  soluble  in  boiling  water,  than  the  liga- 
ments. They  have  a  great  affinity  for  the  phosphate  of  lime ; 
and,  hence,  we  frequently  find  them  hardened  and  having  small 
pieces  of  bone  in  them,  where  they  run  over  bony  trochleae. 

*  A  knowledge  of  the  disposition  in  tendons  to  augment  their  powers  of  circu- 
lation on  being  inflamed,  together  with  the  late  Dr.  Physick's  great  success  in 
the  treatment  of  unnatural  joints  by  a  seton  passed  through  the  cavity  of  the 
fracture,  induced  me  in  a  late  tour  of  service  at  the  alms-house  to  try  the  effect 
of  a  similar  plan  upon  a  ruptured  tendo-achillis;  which,  from  the  long  period 
since  the  accident  happened,  did  not  promise  a  cure  on  the  ordinary  principles 
of  treatment.  A  seton  of  silk  riband  was  accordingly  introduced,  and  kept  in 
its  place  for  six  weeks  and  a  half.  It  produced  considerable  pain,  tumefaction, 
and  inflammation,  but  was  followed  by  a  perfect  reunion  of  the  ruptured  ends  of 
the  tendon. — Chapman's  Mod.  and  Phys.  Journal,  for  July,  1826.  For  a  highly 
interesting  series  of  experiments  on  animals,  undertaken  at  my  suggestion,  to 
illustrate  the  same  thing,  see  An  Essay  for  the  Degree  of  Doctor  of  Medicine, 
by  R.  L.  Fearn,  Id.  April  9,  1827. 

VOL.  L— 31 


BOOK  III. 


PART  II. 

Special  Anatomy  of  Muscles* 

CHAPTER  I. 

MUSCLES  OF  THE  HEAD  AND  NECK. 
SECT.  I.— MUSCLES  OF  THE  FACE. 

Occipito-Frontatis. 

THE  occipito-frontalis,  a  single  muscle,  consists  of  two  symme- 
trical parts,  coming  from  the  back  of  the  head,  and  inserted  into 

*  I  may  here  mention,  once  for  all,  in  regard  to  the  muscular  system,  that 
though  the  very  rigid  mode  of  description  adopted  by  anatomists  may  lead  the 
inexperienced  student  to  infer  that  there  are  no  departures  from  a  common 
standard,  and  that  one  invariable  type  for  the  muscles  prevails  in  all  human  be- 
ings; yet  there  will  be  found  upon  actual  dissection  occasional  disagreements 
with  the  best  established  descriptions,  and  which  it  is  of  some  use  to  know. 
Some  of  these  departures  are  common  enough,  others  very  rare;  and  they  con- 
sist either  in  a  deficiency  or  a  redundancy  of  muscles.  Wishing  not  to  give  false 
ideas  of  their  importance  and  frequency,  and,  indeed,  fearful  of  doing  so,  they 
are  purposely  introduced  subordinately  in  notes:  many  of  them  have  been  ob- 
served by  me  personally,  others  are  recorded  in  different  medical  writings,  and 
for  the  remainder  I  am  indebted  to  the  learned  treatises  on  anatomy  of  T.  Soem- 
mering  and  J.  F.  Meckel. 

No  part  of  the  muscular  system  varies  more  in  different  subjects  than  the  mus- 
cles of  the  back;  but,  as  it  would  be  useless  to  enter  fully  on  such  trivial  details, 
they  have  been  passed  by,  except  in  a  few  instances. 


364  MUSCLES. 

the  front  of  it.  It  is  superficial,  being  placed  immediately  below 
the  skin  of  the  scalp,  and  has  four  bellies  of  muscular  fibres,  two 
behind  and  two  before,  connected  by  a  thin  tendon,  which  covers 
all  the  top  of  the  head.  The  tendon  adheres  by  a  short  cellular 
tissue,  having  no  adeps,  to  the  pericranium  below,  and  is  at- 
tached to  the  common  integuments  above.  The  common  in- 
teguments on  the  hairy  scalp  are  formed  by  skin  and  by  a 
closely  adhering,  and,  indeed,  almost  inseparable  layer  of 
granulated  adeps, 'intermixed  with  the  capsules  of  the  hairs. 

This  muscle  arises  from  the  superior  semicircular  ridges  of 
the  os  occipitis  by  tendinous  and  fleshy  fibres,  which  form  two 
distinct  bellies  (musculus  occipitalis)  about  an  inch  and  a  half 
long,  one  on  each  side  of  the  bone.  Its  tendon,  when  carefully 
traced,  will  be  found  terminating  a  little  in  front  of  the  coronal 
suture,  in  the  two  anterior  fleshy  bellies  (musculus  frontalis) 
which  cover  the  whole  front  part  of  the  os  frontis.  The  internal 
edges  of  these  latter  are  in  conjunction  below. 

It  is  inserted,  on  each  side,  fleshy,  into  the  superior  margin 
of  the  orbicularis  oculi  and  of  the  corrugator  supercilii;  and,. by 
its  nasal  slip,  into  each  internal  angular  process  of  the  os  frontis, 
and  into  the  root  of  the  os  nasi. 

It  pulls  the  skin  of  the  head  backwards  and  forwards,  and 
throws  that  of  the  forehead  into  horizontal  wrinkles.  It  also 
elevates  the  supercilia.* 


Compressor  JVaris. 

The  compressor  naris  arises  by  a  pointed  beginning  from  the 
root  of  the  ala  nasi,  and  spreads  like  a  fan  over  the  lateral  parts 
of  the  nose  below;  it  is  inserted  into  its  fellow  of  the  opposite 
side  on  the  dorsum  of.  the  nose,  and  into  the  lower  part  of  the 
os  nasi,  where  it  is  connected  with  the  nasal  slip  of  the  occipito- 
frontalis. 

This  muscle  consists  of  thin  and  pale  fibres  placed  immediate- 
ly under  the  skin.  If  it  act  from'both  extremities,  by  its  curved 
fibres  being  made  straight,  it  will  compress  the  nostril;  but  if  it 

*  Varieties.  Its  fleshy  portion  is  said  to  have  covered,  in  some  instances,  the 
whole  skull-cap. 


MUSCLES  OF  THE  NECK. 

act  from  its  dorsal  margin,  assisted  by  the  nasal  slip  of  the  occi- 
pito-frontalis,  it  will  dilate  the  ala  nasi,  and  has,  therefore,  been 
called  dilatans  nasum  by  Columbus. 

Orbicularis,  or  Sphincter  Palpebrarum. 

The  orbicularis  oculi  or  palpebrarum  is  a  broad  circular 
muscle,  lying  immediately  under  the  skin  of  the  eyelids,  and 
over  the  tarsi  cartilages.  It  is  much  connected  with  essential 
points  in  the  anatomy  of  the  eyelid. 

Its  diameter  exceeds  that  of  the  orbit,  by  from  four  to  eight 
lines  all  around.  The  fixed  point  of  this  muscle  is  principally 
the  ligamentum  palpebrale  internutn  and  the  internal  canthus 
of  the  orbit ;  for,  in  the  greater  part  of  its  extent,  besides,  it  is 
only  loosely  attached  to  the  parts  below. 

The  orbicularis  arises,  by  short  tendinous  fibres,  from  the  up- 
per end  of  the  nasal  process  of  the  os  maxillare  superius,  from 
the  internal  angular  process  of  the  os  frontis,  and  from  the  con- 
tiguous part  of  the  os  unguis.  It  also  arises  along  the  whole 
superior  margin  of  the  internal  palpebral  ligament. 

The  fibres  from  this  origin  compose  the  lamina  of  the  upper 
eyelid.  They  may  be  traced,  thence,  around  to  the  lower  eye- 
lid, and  are  found  again  terminating  at  the  internal  canthus  of 
the  orbit,  where  they  are  fixed  into  the  anterior  margin  of  the 
orbitar  process  of  the  upper  maxillary  bone,  into  the  corre- 
sponding ridge  of  its  nasal  process,  and  into  the  inferior  margin 
of  the  palpebral  ligament. 

The  temporal  portion  of  this  muscle  is  attached  to  the  tem- 
poral fascia,  so  as  to  prevent  it  from  being  much  displaced.  It 
is,  therefore,  obvious  that  the  effect  of  the  contraction  of  the 
upper  and  of  the  lower  half  of  the  muscle  will  be  to  bring  the 
eyelids  together.  The  fulcrum  of  motion  is  the  internal  or  na- 
sal side,  as  manifested  by  the  radiated  wrinkling  of  the  skin  at 
that  point. 

The  interior  portion  of  this  muscle,  which  is  laid  upon  the 
tarsi  cartilages,  is  called  Ciliaris  by  Albinus:  this  distinction, 
which  is  too  arbitrary,  is  now  abandoned. 


31* 


36(>  MUSCLES. 

The  Corrugator  Super  citti. 

This  muscle  is  placed  beneath  the  upper  margin  of  the  or- 
bicularis,  at  its  internal  extremity;  by  which,  and  by  the  adja- 
cent portion  of  the  occipito-frontalis,  it  is  concealed. 

It  arises  from  the  internal  angular  process  of  the  os  frontis, 
and  going  outwards  and  a  little  upwards,  its  fibres  are  lost  in 
the  inferior  margin  of  the  occipito-frontalis  and  in  the  superior 
of  the  orbicularis. 

It  draws  the  eyebrow  and  the  skin  of  the  forehead  into  ver- 
tical wrinkles,  and  also  draws  them  over  the  eye  so  as  to  over- 
shadow it. 


The  Levator  Labii  Superioris  et  Alec  Nasi, 

Is  fixed  just  at  the  side  of  the  nose.  It  arises  by  a  pointed 
production  from  the  nasal  process  of  the  superior  maxillary 
bone  at  the  internal  canthus  of  the  eye,  and  by  a  broad  origin 
from  the  anterior  margin  of  the  orbitar  process  of  the  same 
bone.  Passing  downwards,  it  is  inserted  into  the  side  of  the  ala 
nasi,  and  into  the  upper  lip,  being  narrower  below  than  above. 
The  part  of  this  muscle  which  comes  from  the  orbitar  process 
is  so  distinct,  that  Albinus  and  the  continental  anatomists  give 
it  the  exclusive  name  of  Levator  Labii  Superioris. 

It  draws  the  upper  lip  and  the  ala  nasi  upwards. 

Just  beneath  this  muscle  there  is  sometimes  a  fasciculus, 
called  the  Anornalus  Faciei  of  Albinus,  which  is  attached  by 
one  end  to  the  upper  jaw  near  the  canine  fossa,  and  by  the 
other  to  the  upper  lip. 

The  Levator  JJnguli  Ori&, 

Is  a  small  muscle,  concealed  very  much  by  the  last;  it  arises 
from  the  anterior  part  of  the  superior  maxillary  bone,  between 
the  foramen  infra-oibitarium  and  the  first  small  grinder,  and  is. 
inserted  into  the  corner  of  the  mouth. 

It  raises  the  angle  of  the  mouth. 


MUSCLES  OF  THE  FACE.  367 


The  Zygomaticus  Minor, 

Is  a  small  muscle,  arising  from  the  fore  part  of  the  os  make  ; 
it  descends  obliquely,  and  is  inserted  into  the  upper  lip  just 
above  the  corner  of  the  mouth.* 


Zygomaticus  Major, 

Is  just  on  the  outside  of  the  last,  and  is  much  larger.  It 
arises  from  the  malar  bone,  externally,  at  its  posterior  inferior 
part,  just  above  the  lower  eqlge,  where  this  bone  contributes  to 
form  the  zygoma.  It  passes  obliquely  downwards  to  be  in- 
serted into  the  corner  of  the  mouth,  and  runs  into  the  depressor 
anguli  oris. 

The  last  two  muscles  draw  the  corner  of  the  mouth  towards 
the  cheek  bone,  or  obliquely  upwards  and  outwards,  as  in 
smiling. 

The  Depressor  Labii  Superioris  et  Alee  JVasi, 

Is  concealed  by  the  orbicularis  oris,  and  the  levator  labii  su- 
perioris  et  alae  nasi.  To  get  a  view  of  it,  the  upper  lip  must 
be  inverted,  and  the  lining  membrane  of  the  mouth  removed 
on  the  side  of  the  frsenurn  of  the  lip.  This  muscle  arises  from 
the  inferior  part  of  the  upper  maxilla  in  front  of  the  alveolar 
processes  for  the  dens  caninus  and  the  incisores,  and  is  inserted 
into  the  side  of  the  ala  nasi,  and  into  the  contiguous  part  of  the 
upper  lip. 

It  depresses  the  upper  lip  and  the  ala  nasi.. 

The  Depressor  Anguli  Oris, 

Arises  broad  and  fleshy  from  the  base  of  the  lower  jaw  or> 
the  side  of  the  chin;  being  somewhat  triangular,  its  apex  is  in- 
serted into  the  corner  of  the  mouth. 

This  muscle  draws  the  corner  of  the  mouth  downwards.     It 

*  Varieties.  Frequently  it  is  deficient;  sometimes  it  is  a  fasciculus  of  the  or- 
bicularis oculi;  sometimes  it  is  double;  sometimes  it  does  not  reach  the  corner 
of  the  mouth.. 


368  MUSCLES. 

lies  immediately  under  the  skin,  and  blends  above  with  the  zy- 
gomaticus  major  and  with  the  levator  anguli  oris. 

The  Depressor  Labii  Inferioris, 

Is  in  part  beneath  the  last  muscle,  and,  like  it,  arises  broad 
and  fleshy  from  the  basis  of  the  lower  jaw  on  the  side  of  the 
chin;  its  fibres  pass  obliquely  upwards  and  inwards,  and  are  in- 
serted into  the  whole  side  of  the  lower  lip. 

It  draws  the  lip  downwards. 

These  last  two  muscles  are  much  obscured  by  being  mixed 
with  a  quantity  of  adipose  matter ;  the  skin,  also,  is  closely 
blended  with  them,  and  the  roots  of  the  beard  penetrate  be- 
tween the  intervals  of  their  fibres.* 


The  Levator  Menti,  or  Labii  Inferioris, 

Being  placed  beneath  the  depressor  labii  inferioris,  is  demon- 
strated by  turning  downwards  the  lower  lip  and  dissecting  away 
its  lining  membrane  on  the  side  of  the  fraenum;  it  will  then  be 
seen  to  arise  in  front  of  the  alveolar  processes  of  the  external  in- 
cisor and  the  canine  tooth,  and,  passing  obliquely  downwards, 
to  be  inserted  into  the  lower  lip. 

It  elevates  the  lower  lip. 


The  Buccinator, 

Arises  from  the  root  of  the  coronoid  process  of  the  lower 
maxilla ;  from  the  back  part  of  the  upper  maxilla  near  the  pte- 
rygoid  process  of  the  sphenoid  bone,  and  from  the  roots  of  the 
alveolar  processes  of  both  the  upper  and  the  lower  maxillary 
bone,  as  far  forwards  as  the  denies  bicuspides.  It  is  inserted 
into  the  corner  of  the  mouth,  and  into  the  contiguous  parts  of 
the  upper  and  lower  lips. 

It  draws  the  corner  of  the  mouth  directly  backwards. 

*  Varieties.     Its  exterior  border  is  often  formed  by  the  Platysma  Myodes. 


MUSCLES  OF  THE  FACE.  369 


The  Orbicular  is  0m, 

Is  a  circular  musclejust  beneath  the  skin,  much  blended  with 
adipose  matter  externally,  but  more  plain  on  the  surface  conti- 
guous to  the  lining  membrane  of  the  mouth.  It  constitutes  a 
considerable  part  of  the  thickness  of  the  lips,  and  surrounds 
the  mouth  entirely.  It  has  no  bony  origin,  but  arises  from  the 
fibres  of  the  several  muscles  which  join  each  other  at  the  cor- 
ner of  the  mouth,  and  therefore  consists  of  two  semicircular 
planes,  one  for  the  upper  and  the  other  for  the  lower  lip. 

It  is  the  antagonist  to  most  of  the  other  muscles  of  the  mouth. 
From  its  superior  part  a  pyramidal  slip  goes  to  the  tip  of  the 
nose,  being  called,  by  Albinus,  Nasalis  Labii  Superioris. 


Masseter. 

The  masseter  is  placed  between  the  skin  and  the  ramus  of 
the  lower  jaw;  it  is  of  an  oblong  shape,  and  evidently  consists 
of  two  portions,  an  external  and  an  internal,  which  may  be 
readily  recognised  by  the  course  of  their  fibres  as  they  decus- 
sate. 

As  a  whole,  it  arises,  tendinous  and  fleshy,  from  the  malar 
process  of  the  maxillare  superius;  from  the  inferior  edge  of  the 
malar  bone,  between  the  maxillary  and  the  zygomatic  sutures, 
and  from  the  zygomatic  process  of  the  temporal  bone.  Of  its 
two  portions,  the  internal  is  the  smaller,  and  is  inserted  tendi- 
nous into  the  outer  part  of  the  root  of  the  coronoid  process  of 
the  lower  jaw;  while  the  external  extends  from  the  malar  bone 
to  the  angle  of  the  lower  jaw,  where  it  is  inserted  tendinous 
and  fleshy.  A  part  of  the  internal  portion  may  be  seen  at  the 
zygomatic  suture,  behind  the  external,  without  the  latter  being 
raised  up. 

When  both  portions  act  together,  they  close  the  jaws:  the 
external,  alone,  also  draw's  the  jaw  forwards;  and  the  internal, 
alone,  will  also  draw  it  backwards. 


370  MUSCLES. 


•>  Temporally. 

The  temporal  muscle  is  placed  on  the  side  of  the  head,  and 
occupies  its  middle  inferior  region.  It  is  covered  externally 
by  the  Fascia  Temporalis,  a  thick,  dense,  tendinous  membrane; 
which  arises  by  the  semicircular  ridge  on  the  side  of  the  cra- 
nium, and  is  inserted  into  the  upper  margin  of  the  zygoma. 

The  temporal  muscle  arises  from  the  inner  face  of  this  fas- 
cia; from  the  whole  length  of  the  semicircular  ridge  on  the 
side  of  the  os  frontis  and  parietale;  and  from  the  surface  of  the 
cranium  between  this  ridge  and  the  zygoma,  including  the  part 
contributed  by  the  frontal  bone,  the  parietal,  the  squamous  por- 
tion of  the  temporal,  and  the  sphenoid.  This  muscle  also  re- 
ceives an  accession  of  fleshy  fibres  from  the  internal  face  of 
the  zygoma. 

From  this  extensive  origin  the  fibres  converge  towards  the 
zygoma,  and  passing  beneath  it,  are  inserted  tendinous  into  the 
coronoid  process  of  the  lower  jaw,  so  as  to  surround  it  on  eve- 
ry side;  some  of  these  tendinous  fibres  go  down  in  front  almost 
to  the  last  dens  molaris. 

It  pulls  the  lower  jaw  directly  upwards* 

Pterygoideus  Externus* 

The  external  pterygoid  muscle,  so  called  from  its  position, 
arises  fleshy  from  the  outer  side  of  the  external  pterygoid  pro- 
cess of  the  sphenoid  bone,  and  from  the  adjoining  surfaces  of 
the  same  bone  by  its  spinous  and  temporal  processes;  also, 
from  the  tuber  of  the  upper  maxillary. 

It  passes  outwards  and  backwards  horizontally,  and  is  in- 
serted into  the  inner  side  of  the  neck  of  the  inferior  maxilla, 
and  into  the  capsular  ligament  of  the  articulation. 

When  the  muscles  of  the  opposite  sides  act  together,  they 
draw  the  lower  jaw  forwards,  but  if  alternately,  they  give  it  a 
grinding  motion.* 

*  Varieties.     I  have  seen,  in  one  case,  this  muscle  continued  into  the  inferior 
margin  of  the  temporal. 


MUSCLES  OF  THE  NECK.  371 


Pterygoideus  Internus,. 

The  Internal  Pterygoid  muscle  arises  by  tendinous  and  fleshy 
fibres  from  the  internal  pterygoid  process  of  the  sphenoid  bone, 
along  the  outer  margin  of  the  Eustachian  tube,  and  from  the 
greater  part  of  the  pterygoid  fossa.  Passing  downwards  and 
backwards,  it  is  inserted  tendinous  and  fleshy  into  the  internal 
face  of  the  angle  of  the  lower  jaw. 

When  the  muscles  of  the  opposite  sides  act,  they  close  the 
jaw. 

SECT.  H. MUSCLES  OF  THE  NECK. 

Of  the  Fascia  Superficialis  CoIlL 

Between  the  skin  of  the  neck  and  its  superficial  muscles, 
may  be  observed  a  layer  of  compact  cellular  substance,  the 
consistence  of  which  is  more  strongly  marked  in  some  subjects 
than  in  others.  It  is  the  continuation  of  the  same  membrane 
which  is  spread  upon  the  external  abdominal  muscles,  and  is 
called  there  the  Fascia  Superficialis  Abdominis.  Passing  from 
the  abdomen  over  the  thorax,  it  adheres  to  the  clavicles  and 
sternum,  but  not  very  strongly;  it  then  goes  from  them  over  the 
neck  to  the  face,  being  slightly  fastened  to  the  base  of  the  lower 
jaw  in  advance  of  the  masseter  muscle. 

It  is  spread  over  the  submaxillary  and  parotid  glands,  is  in 
many  subjects  strongly  marked  there  by  its  fibrous  character ; 
and  sends  down  partitions  between  their  lobules,  as  well  as  be- 
tween the  muscles  and  their  fasciculi;  thereby  forming  sheaths 
for  the  same.  By  these  partitions  it  communicates  with  the 
fascia  profunda  colli.  Above,  it  is  fixed  to  the  mastoid  process, 
to  the  meatus  auditorius  externus,  and  to  the  zygoma.  Just 
above  the  latter  it  adheres  to  the  fascia  temporalis,  and  a  thin 
layer  of  fat  intervenes  between  them.  This  fascia  is  more 
strongly  characterized  about  the  parotid  gland  and  lower  jaw 
than  elsewhere.  It  is  remarkably  distinct  in  the  fretus  at  full 
time,  the  sheaths,  which  it  forms  for  the  muscles,  being  then 
very  clear  of  adipose  matter,  and  semi-diaphanous. 


372  MUSCLES. 

The  Platysma  Myodes, 

Or  the  Musculus  Cutaneus,  lies  upon  the  fascia  superficialis, 
or  rather  is  included  between  two  laminae  of  it,  one  above  and 
the  other  below,  forming  its  sheath,  which  is  very  thin,  espe- 
cially on  the  side  next  to  the  skin.  This  muscle  covers,  by  its 
breadth,  a  very  considerable  portion  of  the  side  of  the  neck; 
and  extends,  obliquely,  from  the  thorax  to  the  face. 

It  arises  from  the  condensed  cellular  membrane  on  the  upper 
part  of  the  pectoralis  major  muscle,  and  of  the  deltoid,  just  be- 
low the  clavicle,  nearly  the  whole  length  of  this  bone.  Its 
fibres  are  much  more  pale  than  those  of  other  voluntary  mus- 
cles, are  collected  into  longitudinal  fasciculi,  constituting  a 
plane  of  scarcely  a  line  in  thickness,  and  terminate  in  the  inte- 
guments of  the  lower  jaw  and  cheek.  It  is  slightly  attached 
to  the  lower  jaw,  and  not  unfrequently  runs  into  the  muscles  of 
the  lower  part  of  the  face. 

When  the  whole  muscle  is  in  action,  it  elevates  the  skin  of 
the  neck.  The  external  jugular  vein  is  seen  running  nearly  in 
the  centre  of  it,  in  the  same  direction  with  the  fibres  of  this 
muscle,  and  between  it  and  the  sterno-cleido  mastoid.* 


The  Sterno-Cleido  Mastoideus, 

Is  beneath,  and  decussates  the  last  muscle.  It  forms  always 
a  prominent  feature  in  the  outline  of  the  neck,  in  passing 
obliquely  from  the  upper  front  part  of  the  thorax  to  the  base  of 
the  cranium. 

It  arises  tendinous  and  fleshy  from  the  edge  of  the  upper 
part  of  the  sternum,  and  fleshy  from  the  sternal  end  of  the  cla- 
vicle. These  origins  are  separated  by  a  considerable  fissure; 
but  they  soon  unite.  It  is  inserted  tendinous  into  the  mastoid 
process,  and  into  the  part  of  the  superior  transverse  ridge  of 
the  cranium  next  to  it. 

It  draws  the  chin  towards  the  sternum. f 

*  Varieties.  In  some  rare  instances  this  muscle  has  been  found  thick  and 
round;  and  instead  of  going  towards  the  face,  inserted  into  the  occiput. 

t  Varieties.  Sometimes  a  fasciculus,  at  its  posterior  margin,  is  presented  in 
a  state  entirely  insulated.  Occasionally,  its  lower  extremity  has  been  observed 


MUSCLES  OF  THE  NECK.  373 


Of  the  Fascia  Profunda  Cotti. 

When  the  origin  of  the  sterno-cleido  mastoideus  is  turned  to 
one  side,  the  Fascia  Profunda  of  the  neck  is  seen  beneath  the 
fascia  superficialis,  and  somewhat  separated  from  it  by  a  lami- 
na of  cellular  adipose  matter.  This  membrane  arises  from  the 
larynx,  forms  a  thin  capsule  to  the  thyroid  gland,  and,  being 
closely  attached  to  its  inferior  margin,  descends  by  investing 
the  sterno-hyoid  and  thyroid  muscles,  being  well  seen  on 
their  anterior  surfaces.  It  is  firmly  fastened  to  the  upper  edge 
of  the  sternum,  to  the  sternal  end  of  the  clavicles,  and  to  the 
cartilages  of  the  first  ribs,  forming  an  elastic  and  resisting 
membrane  from  the  larynx  to  the  thorax.  By  turning  off  the 
sterno-hyoid  and  thyroid  muscles  from  their  attachment  to  the 
sternum,  the  fascia  profunda  will  be  seen  still  more  distinctly, 
passing  behind  them  from  the  inferior  margin  of  the  thyroid 
gland,  to  the  upper  bone  of  the  sternum:  this  lamina  of  it  is  in- 
serted into  the  sternum,  twelve  or  fifteen  lines  below  the  upper 
edge.  It  encloses  or  surrounds  the  transverse  vein  and  the  ar- 
teria  innominata.  Beneath  the  fascia  profunda,  are  the  tra- 
chea, the  roots  of  the  arteries  of  the  head  and  upper  extremi- 
ties and  the  trunks  of  their  veins.  There  is  much  loose 
cellular  and  adipose  matter  placed  at  the  lower  part  of  the 
neck,  beneath  this  fascia  ;  and  between  it  and  the  trachea; 
through  which  the  thyroid  veins  with  their  ramifications  pass. 
This  last  circumstance  must  always  render  suppurations  and 
operations  in  the  part  highly  dangerous,  as  the  pus  will  form 
fistulas  under  the  sternum;  moreover,  the  continual  motion  of  the 
part  in  respiration,  prevents  adhesions  from  forming,  and,  there- 
fore, disposes  to  ulceration.  An  ingenious  idea  on  the  uses  of  this 
fascia  and  of  the  sterno-hyoid  and  thyroid  muscles  as  connect- 
ed with  it,  was  suggested  by  the  late  Allen  Burns:  he  con- 
ceived that  they  were  a  defence  to  the  upper  part  of  the  thorax, 
and  sustained,  in  inspiration,  the  atmospheric  pressure,  which, 
without  them,  would  fall  upon  the  trachea  and  produce  difficul- 

to  reach  as  far  as  the  rcctus  abcbminis  muscle,  and  even  to  the  point  of  the  third 
bone  of  the  sternum.  The  fissure  between  the  sternal  and  clavicular  portions  in 
mammiferous  animals,  i.-?,  naturally,  so  much  extended,  as  to  produce  two  dis- 
tinct muscles. 

VOL.  I.— 32 


374  MUSCLES. 

ty  of  breathing,  from  the  air  not  passing  through  the  larynx 
sufficiently  rapidly  to  keep  pace  with  the  dilatation  of  the  thorax. 
He  illustrates  the  opinion  by  a  case  very  much  in  point,  of  a  gen- 
tleman who  had  lost  this  fascia  and  the  muscles  by  suppuration, 
and  who  was  afterwards  incommoded  by  atmospheric  pressure 
upon  the  trachea  at  this  place.*  Mr.  Velpeau,  on  the  contrary, 
asserts  that  cutting  through  it  in  opening  abscesses  and  in  ope- 
rations has  no  such  consequence.t 

The  external  borders  of  the  fascia  profunda  are  continued 
into  the  sheaths  of  the  great  vessels  of  the  neck.  It  and  the 
fascia  superficialis  are  also  continuous  with  one  another  along 
the  anterior  edge  of  the  sterno-cleido  mastoideus. 

Within  the  inferior  maxilla,  at  its  angle,  a  ligamentous  ex- 
pansion arises  at  the  pterygoideus  externus  muscle,  and  is 
spread  out  between  the  styloid  process,  and  the  ramus  of  the  low- 
er jaw.  This  membrane,  described  as  the  stylo-maxillary  liga- 
ment, is  joined  at  its  inferior  edge  by  the  fascia  superficialis, 
just  before  the  upper  part  of  the  sterno-mastoideus,  and  which  in- 
creases its  breadth  downwards  in  the  neck,  giving  it  somewhat 
the  condition  of  a  vertical  septum  of  that  region;  at  its  lower  edge 
it  runs  into  the  theca  of  the  great  vessels  of  the  neck.  Through 
its  lower  part  penetrate  the  stylo-hyoideus  and  digastricus 
muscles,  and  the  upper  part  separates  the  parotid  from  the 
sub-maxillary  gland.  It  is  felt  like  a  cord  extending  downwards 
and  backwards  below  the  angle  of  the  maxillainferior.  It 
is  connected  at  its  internal  edge  with  the  compages  of  the 
nerves  and  vessels  of  the  part,  in  such  a  manner  as  to  forbid 
description,  but  the  practical  anatomist  will  find  no  difficulty 
in  discovering  and  understanding  it. 

Below  this  septum,  the  round  ligament,  like  a  nerve,  passes 
from  the  extremity  of  the  styloid  process  to  the  appendix  of 
the  os  hvoides. 

The  fascia  profunda  colli  is  also  well  marked  in  the  foetus, 
and  not  much  blended  with  adipose  matter.  It,  like  the  fascia 
superficialis,  is  only  the  sheath  the  for  muscles  which  it  sur- 

*  The  late  Dr.  La\vrcnce  informco!  inc  that  the  fascia  profumla  is  well  developed 
in  the  neck  of  a  cat,  end  that  having  occasion  to  remcvc  it  in  an  experiment,  the 
respiration  of  the  animal  w;;s  conducted  with  great  difficulty,  amounting  almost 
tt  suffocation.  This  is  a  jrood  confirmation  of  Mr.  Burns's  hypothesis. 

f  Anat.  Chir.  Vol.  i.  p.  438,  2nd  edit. 


MUSCLES  OF  THE  NECK.  375 

rounds,  and  is  called  fascia  from  having  some  development  of 
fibrous  matter  in  its  substance. 


The  Sterno-Hyoideus, 

Arises  thin  and  fleshy  on  the  interior  of  the  thorax  from  the 
approximated  surfaces  of  the  cartilage  of  the  first  rib,  the  cla- 
vicle, and  the  first  bone  of  the  sternum;  it  passes  upwards  some- 
what obliquely,  and  is  inserted  into  the  inferior  edge  of  the  base 
of  the  os  hyoides.  Its  lower  end  is  covered  by  the  sterno-mas- 
toideus. 

It  draws  the  os  hyoides  towards  the  sternum.* 

The  Sterno-  Thyroideus, 

Is  beneath  the  last,  and  concealed,  in  a  considerable  degree, 
by  it.  It  arises  fleshy  from  the  interior  surface  of  the  sternum, 
about  an  inch  below  its  upper  margin,  and  from  the  cartilage  of 
the  first  rib;  diminishing  somewhat  in  breadth,  as  it  ascends,  it 
Is  inserted  obliquely  into  the  side  of  the  thyroid  cartilage. 

It  draws  this  cartilage  towards  the  sternum.t 

The  Thyro-Hyoideus. 

Arises  obliquely  from  the  side  of  the  Thyroid  Cartilage  ex- 
ternally, and  is  inserted  into  a  part  of  the  base,  and  into  nearly 
all  the  cornu  of  the  os  hyoides.  It  seems  almost  like  a  conti- 
nuation of  the  Sterno-Thyroideus, 

Its  use  is  to  approximate  the  os  hyoides  and  the  thyroid  car- 
tilage, in  doing  which  it  has  the  effect  of  planting  the  epiglottis 
against  the  root  of  the  tongue,  and  of  drawing  the  cricoid  and 

*  Varieties*  Sometimes  it  arises  frprn  the  middle  of  the  clavicle;  it  is  double, 
or  is  confounded  below  with  the  next  muscle. 

t  Varieties.  Sometimes  there  are  two  of  these  muscles,  one  placed  above  the 
other;  sometimes  it  runs  into  the  inferior  constrictor  of  the  pharynx;  sometimes 
it  runs  into  the  posterior  margin  of  the  thyro-hyoid  muscle;  sometimes  the  mus- 
cle on  one  side  is  united  to  the  other  by  transverse  fibres.  1  have,  in  one  in- 
stance, Jan.  1,  1839,  seen  a  slip  at  the  external  margin  of  this  muscle  which 
arising  from  the  cartilage  of  the  first  rib,  ascended  in  front  of  "the  great  vessels' 
and  was  inserted  into  their  sheath  on  a  level  with  the  thyroid  cartilage. 


376  MUSCLES. 

the  arytenoid  cartilages  against  it,  so  that  the  opening  of  the 
glottis  is  protected.* 

The  Omo-Hyoideus, 

Passes  obliquely  across  the  neck,  from  the  superior  edge  of 
the  scapula  to  the  os  hyoides.  It  is  a  thin,  narrow  muscle,  di- 
vided into  two  bellies,  one  at  each  end,  by  an  intermediate  ten- 
don; its  inferior  part  is  concealed  by  the  trapezius  muscle;  its 
middle,  where  the  tendon  exists,  crosses  the  great  vessels  of  the 
neck,  and  is  covered  by  the  slerno-eleido-mastoid  muscle;  and 
its  upper  extremity  is  overlapped  by  the  platysma  myodes. 

It  arises  from  the  scapula  just  behind  the  notch  in  its  supe- 
rior costa,  and  curving  somewhat  downwards  in  its  course,  it  is 
inserted  into  the  lower  edge  of  the  base  of  the  os  hyoides,  next 
to  its  cornu. 

It  draws  the  os  hyoides  downwards.f 

The  Digastricus, 

Is  placed  at  the  upper  side  of  the  neck,  and  passes  from  the 
back  part  of  the  base  of  the  head  to  the  chin. 

It  arises  principally  fleshy  from  the  fossa  of  the  temporal  bone 
at  the  base  of  the  mastoid  process;  its  middle  is  converted  into 
a  round  tendonj  which  passes  through  the  stylo-hyoideus  mus- 
cle, and  is  fixed  by  a  ligamentous  loop  to  the  cornu  of  the  os 
hyoides.  After  which  another  fleshy  belly  is  formed,  which  is 
inserted  into  the  inside  of  the  base  of  the  maxilla  inferior,  at 
the  side  of  its  symphysis.  It  receives  an  accession  from  the 
base  of  the  os  hyoides. 

Its  use  is  to  draw  the  os  hyoides  upwards  when  its  extremi- 
ties are  fixed,  and,  as  Mr.  Hunter  has  pointed  out,  to  throw  the 
head  backwards,  and  thereby  to  open  the  mouth  when  the  lower 
jaw  is  fixed  upon  a  body  of  the  same  height.J 

*  Varieties.  Its  fibres  sometimes  run  into  those  of  the  middle  constrictor  of 
the  pharynx;  sometimes  they  arise  from  the  cricoid  cartilage;  sometimes  it  is 
continuous  with  the  sterno-thyroideus. 

t  Varieties.  Sometimes  it  is  double,  so  that  besides  the  usual  insertion,  it  has 
one  into  the  side  of  the  tongue. 

t  A  common  variety  in  this  muscle  consists  in  the  mutual  adhesion  of  the 
two  anterior  bellies  belonging  to  the  opposite  sides,  showing  thereby  a  marked 
tendency  to  the  quadruped  arrangement. 


MUSCLES  OF  THE  NECK.  377 


The  Stylo-Hyoideus, 

Is  the  more  superficial  of  the  three  styloid  muscles.  It  arises 
tendinous  from  the  middle  and  inferior  part  of  the  styloid  pro- 
cess of  the  temporal  bone;  and  being  perforated,  as  mentioned, 
by  the  tendon  of  the  digastricus,  is  inserted  tendinous  into  the 
cartilaginous  juncture  of  the  base  and  cornu  of  the  os  hyoides. 

It  draws  the  os  hyoides  upwards  and  backwards.* 


The  Stylo- Glossus, 

Is  within  and  above  the  other;  it  arises  from  the  upper  in- 
ternal part  of  the  styloid  process,  tendinous  and  fleshy,  and  is 
inserted  into  the  side  of  the  root  of  the  tongue,  forming  a  part 
of  its  structure.! 

It  draws  the  tongue  backwards.J 


The  Stylo- Pharyngeus, 

Is  more  deeply  situated  than  either  of  the  other  two  muscles. 
It  arises  from  the  inner  side  of  the  styloid  process  near  its  root, 
and  runs  into  the  side  of  the  pharynx  between  the  middle  and 
upper  constrictors,  opposite  the  tonsil  gland;  it  afterwards  de- 
scends between  the  lining  membrane  of  the  pharynx  and  the 
middle  and  lower  constrictors,  and  is  inserted  into  the  posterior 
margin  of  the  thyroid  cartilage. 

It  draws  the  larynx  and  pharynx  upwards. 


The  Mylo-Hyoideus, 

Forms  the  floor  of  the  mouth  and  suspends  the  tongue;  it 
arises  at  the  root  of  the  alveolar  processes  of  the  lower  jaw, 
from  a  ridge  extending  from  the  last  dens  molaris  to  the  chin. 
Its  fibres  converge  towards  a  white  tendinous  line  placed  be- 

.*  Varieties.     This  muscle  is  frequently  double. 
t  See  Tongue. 

t  Varieties.  J.  F.  Meckel  says,  that  on  one  occasion  he  found  it  double  on 
both  sides. 

32* 


378  MUSCLES. 

tween  it  and  its  fellow,  and  reaching  from  the  base  of  the  os 
hyoides  to  the  chin.  This  muscle  is  concealed  by  the  anterior 
belly  of  the  digastricus.  When  it  contracts,  it  draws  the  os 
hyoides  upwards  and  projects  the  tongue.* 

The  Genio-Hyoideus, 

Is  concealed  by  the  last;  by  turning  over  the  anterior  edge  of 
which,  it  is  seen.  It  arises  tendinous  from  the  tubercle  on  the 
posterior  side  of  the  symphysis  of  the  lower  jaw;  and,  in- 
creasing somewhat  in  breadth,  is  inserted  into  the  anterior  part 
of  the  base  of  the  os  hyoides. 

It  draws  the  os  hyoides  upwards  and  forwards.! 

(For  the  muscles  of  the  tongue,  see  Mouth.) 

There  are  seven  pairs  of  muscles,  on  the  front  and  sides  of 
the  cervical  vertebrae,  which  lie  closely  upon  them.  They  are 
named  from  their  situations  and  shapes. 


1.  Longus  Colli. 

The  Longus  Colli  is  next  to  the  middle  line  of  the  vertebrae. 
It  arises  from  the  sides  of  the  bodies  of  the  three  superior  ver- 
tebrae of  the  back,  and  from  the  anterior  edges  of  the  trans- 
verse processes  of  the  five  lower  cervical  vertebrae.  Its  fibres 
pass  somewhat  obliquely  upwards  and  inwards,  to  be  inserted 
into  the  front  of  the  bodies  of  all  the  cervical  vertebras. 

It  bends  the  neck  forwards,  and  to  one  side.J 

*  Varieties.  Sometimes  a  part  of  it  is  inserted  into  the  middle  tendon  of  the 
digastricus,  or  is  joined  with  the  sterno-hyoidcus. 

t  Varieties.  Sometimes  a  distinct  fasciculus  of  this  muscle  is  inserted  into 
the  greater  part  of  the  cornu  of  the  os  hyoides.  Sometimes  the-re  is  but  one 
muscle.  Rarely  it  is  double  on  both  sides. 

t  Varieties.  Sometimes  a  fasciculus  from  the  first  or  second  rib,  or  from  the 
body  of  the  sixth  or  seventh  vertebra  of  the  neck,  joins  it. 


MUSCLES  OF  THE  NECK.  379 


2.  Rectus  Capitis  Anticus  Major, 

Is  placed  on  the  outside  of  the  last.  It  arises  tendinous  and 
fleshy  from  the  fronts  of  the  transverse  processes  of  the  third, 
fourth,  fifth,  and  sixth  cervical  vertebrae;  forms  a  considerable 
fleshy  belly,  and  is  inserted  into  the  cuneiform  process  of  the 
os  occipitis,  just  before  the  condyle.  It  bends  the  head  for- 
wards.* 

3.  Rectus  Capitis  Anticus  Minor. 

This  is  a  very  small  muscle.  It  arises  fleshy  from  the  front 
of  the  first  cervical  vertebra  near  its  transverse  process,  and  is 
inserted  under  the  rectus  major  before  the  root  of  the  condy- 
loid  process  of  the  occipital  bone. 

It  bends  the  head  forwards. 


4.  Rectus  Capitis  Lateralis. 

This  is  also  small,  and  arises  fleshy  from  the  front  of  the 
transverse  process  of  the  atlas.  It  is  inserted,  tendinous  and 
fleshy,  at  the  outside  of  the  condyle  of  the  occiput,  into  the 
ridge  leading  from  it  to  the  mastoid  process. 

It  pulls  the  head  a  little  to  one  side.t 

5.  Scalenus  Prior,  or  Jlnticus. 

• 

The  scalenus  anticus  arises  by  three  distinct  tendinous  heads 
from  the  transverse  processes  of  the  fourth,  fifth,  and  sixth  cer- 
vical vertebras,  and  is  inserted  tendinous  and  fleshy  into  the 
upper  surface  of  the  first  rib,  just  anteriorly  to  its  middle. 


6.  Scalenus  Medius. 

The  scalenus  medius  arises  by  distinct  tendons  from  the  trans- 
verse processes  of  all  the  cervical  vertebra,  and  is  inserted  ten- 

*  Sometimes  it  also  arises  from  the  first  and  second  vertebrae. 
t  Varieties.     Sometimes  another  muscle  arises  from  the  body  of  the  first  ver- 
tebra of  the  neck. 


380  MUSCLES. 

dinous  and  fleshy  into  the  upper  face  of  the  first  rib,  in  all  the 
space  from  its  middle  to  its  tubercle. 


7.  Scalenus  Posticus. 

The  scalenus  posticus  arises  from  the  transverse  process 
of  the  fifth  and  sixth  cervical  vertebrae,  and  is  inserted  into  the 
upper  face  of  the  second  rib,  just  beyond  its  tubercle. 

The  last  three  muscles  are  concealed  by  the  sterno-cleido 
mastoideus  and  the  anterior  edge  of  the  trapezius.  The  scale- 
nus posticus  is  best  seen  in  dissecting  the  muscles  of  the  spine, 
and  resembles  very  much  one  of  the  class  to  which  Albinus 
gives  the  name  of  Levatores  Costarum. 

All  the  Scaleni  elevate  the  ribs  and  bend  the  neck  to  one 
side.  They  are  particularly  interesting  as  connected  with  the 
course  of  the  large  blood  vessels  and  nerves  of  the  upper  ex- 
tremity.* 


CHAPTER    H. 

MUSCLES  OF  THE  TRUNK. 
SECT.  I. MUSCLES  ON  THE  FRONT  OF  THE  THORAX. 

The  PectoraHs  Major, 

Is  superficial,  and  forms  the  large  swelling  cushion  of  flesh 
under  the  skin  of  the  breast.  It  arises  tendinous  from  the  ante- 
rior face  of  the  first  two  bones  of  the  sternum,  their  whole  length, 
fleshy  from  the  cartilages  of  the  fifth  and  sixth  ribs,  and  by  a 
fleshy  slip  from  the  upper  part  of  the  tendon  of  the  external  ob- 

*  Varieties.  Besides  the  three  scaleni  which  are  described,  there  are  frequent- 
ly supernumerary  muscles  or  fasciculi.  One  of  these,  called  the  Scalenus  Mini- 
mus Albini,  is  between  the  first  two,  and  occasionally  appears  as  a  fasciculus  of 
the  scalenus  anticus,  separated  from  it  by  one  or  more  of  the  brachial  nerves;  it 
is  sometimes  double.  Another  fasciculus,  called  the  Scalenus  Lateralis,  is  be- 
twecn  the  scalenus  medius  and  posticus;  it  comes  from  the  posterior  part  of  the 
rirst  rib,  and  is  inserted  into  the  transverse  process  of  the  fourth,  fifth,  and  sixth 
vertebrae. 


MUSCLES  OF  THE  THORAX.  381 

lique  muscle.  It  arises,  also,  fleshy  from  the  anterior  two- 
thirds  of  the  clavicle.  The  clavicular  and  sternal  portions  of 
the  origin  are  separated  by  an  interval,  giving  the  appearance 
of  two  muscles. 

The  fibres  converge,  and  terminate  by  a  broad,  thin  tendon, 
which  is  inserted  into  a  roughness  on  the  exterior  edge  of  the 
bicipital  fossa  of  the  os  humeri,  and  into  the  fascia  brachialis, 
just  at  the  internal  edge  of  the  deltoid  muscle.  At  this  inser- 
tion it  adheres  to  the  tendon  of  the  latissimus  dorsi.  The  un- 
der edge  of  the  muscle,  near  its  insertion,  is  folded  inwards  and 
upwards,  which  gives  the  rounded  thick  margin  to  the  fore 
part  of  the  axilla.  That  part  of  the  broad  tendon  belonging  to 
the  clavicular  portion  is  inserted  lower  down  than  the  sternal, 
which  produces  a  decussation  of  the  fibres  of  the  tendon. 

The  pectoralis  major  draws  the  arm  inwards  and  forwards; 
and  also  depresses  it  when  it  is  raised.* 

The  Pectoralis  Minor, 

Is  brought  into  view  by  raising  the  last  muscle.  It  is  com- 
paratively small,  and  somewhat  triangular.  Arising  by  thin 
tendinous  digitations  from  the  upper  edges  of  the  third,  fourth, 
and  fifth  ribs,  it  soon  becomes  fleshy,  and  is  inserted,  by  a  short 
flat  tendon,  into  the  inner  facet  of  the  coracoid  process  of  the 
scapula.  Its  use  is  to  draw  the  scapula  inwards  and  down- 
wards.f 

*  Varieties.  Sometimes  a  single  fasciculus  arises  from  the  eighth  rib,  which 
ascends  towards  the  os  humeri,  has  a  tendon  in  its  centre,  and  finally  joins  with 
the  tendon  of  the  pectoralis  minor; — sometimes  this  muscle  attaches  a  small  fas- 
ciculus to  the  brachialis  internus; — sometimes  there  is  a  small  square  plane  of 
muscular  fibres  on  its  front  surface,  decussating  the  fibres  at  right  angles ; — 
sometimes  a  fasciculus  almost  cylindrical  proceeds  from  it  towards  the  axilla, 
and,  being  changed  into  a  long  tendon,  is  inserted  into  the  internal  tuberosity  of 
the  os  humeri.  Supernumerary  fasciculi  are  also  found  going  from  one  rib  to 
another,  or  towards  the  sternum;  sometimes  its  tendon  detaches  a  fasciculus, 
which,  crossing  the  insertion  of  the  muscle,  covers  the  bicipital  groove  of  the  oa 
humeri  like  a  bridge,  is  blended  with  the  tendon  of  the  supra-spinatus,  and  in- 
creases  the  thickness  of  the  capsular  ligament  of  the  shoulder  joint.  In  a  mus- 
cular male  subject,  black,  it  was  entirely  deficient,  except  the  external  clavicular 
half.  The  pectoralis  minor  was  wholly  wanting  in  the  same.  Deer.  1837. 

t  Varieties.  Sometimes  it  sends  a  fleshy  fasciculus  to  the  tendinous  origin 
of  the  coraco-brachialis.  Sometimes,  below  it,  there  is  a  third  pectoral  muscle, 


382  MUSCLES. 


The  Subclavius, 

Is  a  small  muscle,  placed  immediately  under  the  clavicle.  It 
arises  from  the  cartilage  of  the  first  rib,  and  is  inserted  into  the 
inferior  face  of  the  clavicle,  from  near  the  sternum,  to  the  co- 
noid ligament,  which  connects  the  coracoid  process  and  the 
clavicle  together.  It  draws  the  clavicle  downwards.* 


The  Serratus  Magnus,  or  Serratus  Major  Anticus, 

Is  a  broad  muscle,  lying  on  the  sides  of  the  ribs,  between  them 
and  the  scapula,  and  beginning  at  a  line  anterior  to  their  middle. 
It  arises  from  the  nine  upper  ribs  by  fleshy  digitations,  the  su- 
perior one  of  which  seems  almost  like  a  distinct  muscle:  the 
five  lower  are  connected  to  the  obliquus  externus  abdominis, 
the  digitations  of  the  two  muscles  inter-locking  with  each  other. 
The  fibres  converge,  and  are  inserted  into  the  base  of  trie  scapula 
its  whole  length.  Its  action  is  to  draw  the  scapula  forwards. t 


The  Inter costales, 

Fill  up  the  spaces  between  the  ribs.  There  are  two  in  each 
space,  of  which  the  external  arises  from  the  transverse  process 
of  the  vertebra,  and  from  the  inferior  acute  edge  of  the  rib, 
from  its  head  almost  to  its  cartilage,  and  is  inserted  into  the  su- 
perior rounded  edge  of  the  rib  below  for  the  same  distance,  its 
fibres  passing  obliquely  forwards  and  downwards.  The  inter- 
nal intercostal  arises  from  the  inferior  edge  of  the  rib,  beginning 
at  the  sternum,  and  extends  backwards  to  the  angle  of  the  rib; 
it  is  inserted  into  the  superior  rounded  edge  of  the  rib,  below, 

which  arises  from  the  first  and  second  ribs,  and  is  inserted  into  the  coracoid  pro- 
cess; whereby  a  striding  analogy  with  birds  is  established.  Another  variety  has 
also  been  observed  in  the  existence  of  a  fasciculus,  which  comes  from  the  upper 
rib,  and  which,  covered  by  the  little  pectoral  muscle,  is  inserted  into  the  capsular 
ligament  of  the  scapulo-humeral  articulation. 

*  Varieties.  Sometimes  two  muscles  exist;  a  bursa  mucosa  is  formed  between 
its  tendon  and  the  cartilage  of  the  first  rib. 

t  Varieties.  Sometimes,  it  has  ten  or  eleven  origins  ;  the  upper  origin  is  defi- 
cient; the  latter  is  so  distinct  that  it  may  pass  for  a  particular  muscle;  a  wide 
gap  exists  in  the  middle  of  the  muscle,  dividing  it  into  two  distinct  parts. 


MUSCLES  OF  THE  THORAX.  383 

on  its  inner  side,  its  fibres  passing  obliquely  backwards  and 
downwards.     They  draw  the  ribs  together. 


The  Triangular  is  Sterni. 

Is  on  the  posterior  or  cardiac  face  of  the  cartilages  of  the  ribs, 
and  arises  from  the  whole  length  of  the  cartilago  ensiformis  at 
its  edge,  and  from  the  inferior  half  of  the  edge  of  the  second 
bone  of  the  sternum.  The  fibres  go  obliquely  upwards  and 
outwards,  to  be  inserted  into  the  cartilages  of  the  third,  fourth, 
fifth,  and  sixth  ribs  by  fleshy  and  tendmous  digitations.  Its 
use  is  to  depress  the  ribs,  and,  consequently,  to  diminish  the 
cavity  of  the  thorax. 

This  muscle  is  frequently  defective  or  redundant  in  the  num- 
ber of  its  heads,  and  is  commonly  more  or  less  continuous  with 
the  transversalis  abdominis;  but  occasionally  it  is  so  much  so, 
that  the  two  seem  to  make  but  one  muscle,  and  have,  therefore, 
been  called  Sterno-abdominalis,  by  Rosenmuller. 


SECT.  II. MUSCLES  AND  FASCIJE  OF  THE  ABDOMEN. 

Between  the  most  superficial  of  the  abdominal  muscles,  which 
is  the  external  oblique,  and  the  skin,  is  found  the  Fascia  Super- 
ficialis  Abdominis.  In  lean  subjects  it  is  very  distinct,  but  in 
fat  ones  not  so  much  so,  from  being  blended  with  adipose  mat- 
ter. The  laminae  of  it  which  are  next  to  the  muscles,  are  kept, 
in  the  latter  case,  rather  more  free  from  fat  than  the  more  su- 
perficial. It  consists  of  condensed  cellular  substance,  with  very 
little  fibrous  matter  in  it,  and  may  be  considered  as  taking  its 
origin  on  the  front  of  the  thigh,*  and  extending  in  front  of  the 
abdominal  muscles,  as  high  up  as  the  thorax:  indeed,  if  we  are 
disposed  to  trace  it  to  its  whole  extent,  there  is  no  difficulty  in 
following  it  over  the  front  of  the  thorax;  thence  to  the  neck,  as 

*  This  statement  of  origin  is  to  be  viewed  merely  as  an  anatomical  license  for 
descriptive  purposes;  the  most  natural  line  of  origin  is  the  whole  length  of  the 
linea  alba,  and  this  same  line  might  be  considered  as  going  along  the  front  of 
the  sternum  for  the  pectoral  fascia,  and  along  the  middle  of  the  neck  for  its  fascia 
iiiperficialis  and  profunda. 


384  MUSCLES. 

the  fascia  superficial  colli;  and  even  to  the  face.  In  ordinary 
cases  its  desmoid  or  aponeurotic  character  is  very  equivocal,  but 
where  the  parts  about  the  groin  have  been  pressed  upon  and 
thickened  by  the  irritation  of  hernial  protrusion,  it  is  better 
marked.  On  the  thigh  it  is  blended  with  fat;  and  encloses  be- 
tween  its  laminae  the  lymphatic  glands  of  the  groin,  and  the  ex- 
ternal  pudic  vessels  given  off  from  the  femoral  artery,  immedi- 
ately below  Poupart's  ligament.  On  the  tendon  of  the  external 
oblique  it  is  more  condensed;  branches  of  the  femoral  artery 
are  also  seen  in  it  there.  One  longer  and  larger  than  the  others, 
the  arteria  ad  cutem  abdominis  of  Haller,  winds  over  Poupart's 
ligament,  and  runs  upwards  somewhat  in  the  line  of  the  epigas- 
tric artery,  to  be  distributed  to  the  skin  of  the  abdomen :  the  di- 
vision of  it  will  produce  sufficient  hemorrhage  to  require  atten- 
tion. On  the  symphysis  pubis  and  about  the  external  ring  the 
laminae  of  the  fascia  superficialis  are  multiplied,  and  it  has 
more  of  the  character  of  common  adipose  matter,  as  in  most 
cases  the  adeps  there  is  abundant.  From  the  pubes  it  may  be 
traced  as  a  condensed  cellular  membrane  blended  with  the 
ligamentum  suspensorium  along  the  penis  to  its  extremity;  and, 
according  to  Mr.  Colles,  of  Dublin,  when  matter  is  formed  be- 
neath it,  it  is  apt  to  create  fistulous  sores  on  this  organ.  A 
thin  process  of  this  membrane  may  be  traced  along  the  sper- 
matic chord,  and  identified  with  the  tunica  vaginalis  communis. 
This  fascia  is  more  loosely  connected  to  the  parts  beneath  it, 
along  the  anterior  margin  of  Poupart's  ligament,  than  elsewhere, 
which  disposes  femoral  hernia  to  observe  that  course  in  its  in- 
crease. 

The  fascia  Superficialis,  under  the  name  of  Tunica  Abdo- 
minalis,  is  well  developed  in  animals  with  a  large  and  project- 
ing belly,  particularly  in  the  large  rumiriantia  and  the  solipedia. 
It  has  a  yellowish  tinge  in  them,  is  very  elastic  and  strong,  and 
well  calculated  to  support  their  viscera.* 

There  are  five  pairs  of  muscles  called  abdominal;  to  wit,  the 
External  Oblique;  the  Internal  Oblique;  the  Transverse;  the 
Straight;  and  the  Pyramidal.  The  first  three  are  flat  and 
broad,  and  lie  in  layers  one  upon  the  other;  the  other  two  are 
long. 

*  Breschet,  Thesis  sur  L'Hcrnie.     Paris,  1819. 


MUSCLES  OF  THE  ABDOMEN.  385 


1.  The  Obliquus  Externus, 

Arises  from  the  eight  inferior  ribs  by  muscular  and  tendinous 
digitations  attached  near  their  anterior  extremities.  The  first 
head  is  covered  by  a  slip  from  the  pectoralis  major,  the  five 
upper  heads  are  interlocked  with  the  origins  of  the  serratus 
major  anticus,  and  the  three  inferior  with  those  of  the  latissi- 
mus  dorsi.  The  fibres  pass  obliquely  downwards,  and  termi- 
nate in  a  broad  thin  tendon.  This  tendon  extends  over  the 
whole  front  of  the  abdomen,  from  the  lower  end  of  the  second 
bone  of  the  sternum  to  the  symphysis  of  the  pubes. 

This  muscle  is  inserted  into  the  whole  length-  of  the  linea 
jilba;  into  the  anterior  half  or  two-thirds  of  the  crista  of  the  ilium, 
by  muscular  fibres  posteriorly,  and  tendinous  anteriorly;  and, 
from  the  anterior  superior  spinous  process,  the  tendon  extends 
to  the  body  and  to  the  symphysis  of  the  pubes,  forming  thereby 
the  ligament  of  Poupart,  or  the  Crural  Arch. 

In  the  middle  line  of  the  body,  the  tendons  of  the  three  broad 
muscles,  on  both  sides  of  the  abdomen,  unite  to  form  the  Linea 
Alba,  which  extends  from  the  sternum  to  the  pubes.  From 
two  to  three  inches  in  the  adult,  on  either  side  of  the  linea  alba, 
but  more  distant  from  it  above  than  below,  is  another  line,  formed 
by  the  same  tendons,  which  is  the  Linea  Semilunaris.  The 
navel,  which  originally  was  a  hole  for  the  passage  of  the 
umbilical  vessels,  and,  in  the  adult,  is  commonly  depressed  into 
a  pit,  appears  in  the  linea  alba  as  a  protuberance  composed  of 
a  condensed  cellular  membrane.  Just  at  the  navel  there  is  a 
line  crossing  the  linea  alba,  and  extending  from  one  linea  se- 
milunaris  to  the  other;  at  the  lower  end  of  the  Cartilago-Ensi- 
formis,  there  is  another;  and  half-way  between  this  and  the 
navel,  a  third :  about  half-way  between  the  navel  and  the  pubes 
is  a  fourth,  but  it  is  generally  imperfect.  These  are  the  Linear 
Transversoe,  and  they  are  formed  foy  tendinous  matter  in  the 
substance  of  the  recti  muscles,  connecting  them  to  their  tendi- 
nous sheath  in  front. 

The  most  interesting  insertion  of  the  tendon  of  the  external 
oblique,  is  the  portion  constituting  Poupart's  ligament,  or  the 
Crural  Arch.  The  latter  as  it  gets  to  the  pubes  from  the  ilium, 
splits  so  as  to  leave  a  hole  for  the  passage  of  the  Spermatic 

VOL.  I.— 33 


386  MUSCLES. 

Chord  in  the  male,  and  of  the  Round  Ligament  of  the  Uterus  in 
the  female.  This  opening  is  named  the  External  Abdominal 
Ring.  The  tendon  forming  its  upper  boundary  is  inserted  into 
the  symphysis  pubis,  and  into  the  pubes  of  the  opposite  side,  by 
fibres  which  are  interwoven  with  and  decussate  those  of  its  fel- 
low. The  tendon  forming  the  lower  margin  of  the  ring  is  in- 
serted into  the  spine  of  the  pubes,  and  into  its  crislafor  an  inch. 
The  portion  inserted  into  the  crista  of  the  pubes  is  Gimbernat' s 
ligament,  which  it  will  be  readily  understood,  means  only  a 
part  of  the  Crural  Arch. 

The  Ring  in  the  External  Oblique  is  rather  triangular  than 
round;  its  base  is  formed  by  the  body  of  the  pubes,  and  its  point 
is  at  the  place  where  the  tendon  splits.  The  latter  is  kept  from 
parting  still  farther  by  a  fasciculus  of  tendinous  fibres,  which 
runs  across  it  The  sides  of  this  opening  are  called  its  Columns, 
and  from  their  situation,  internal  and  external,  or  upper  and 
lower  Columns.  In  the  female  it  is  oval  and  scarcely  half  an 
inch  long. 

There  are  several  small  round  holes  in  the  tendon  of  this 
muscle,  which  afford  passage  to  nerves  and  to  veins.  When, 
by  the  clearness  of  the  dissection,  the  tendon  has  its  characte- 
ristic gloss  and  polish,  they  are  very  distinct. 

Use.  This  muscle  compresses  the  viscera  of  the  abdomen 
and  brings  the  pelvis  and  thorax  towards  each  other.* 


The  Obliquus  Interims, 

Lies  beneath  the  last,  and  its  fibres  pass  in  a  contrary  direc- 
tion to  the  fibres  of  the  other.  It  arises  tendinous,  by  the  fascia 
lumborum,  from  the  three  inferior  spinous  processes  of  the  loins 
and  from  all  those  of  the  sacrum;  tendinous  and  fleshy,  from  the 
whole  length  of  the  crista  of  the  ilium ;  and  fleshy,  from  the 
upper  half  of  Poupart's  ligament.  Though  the  fibres  of  this 

*  Varieties.  Sometimes  a  considerable  part  of  its  middle  and  anterior  portion 
is  deficient,  a  vitiated  conformation,  to  which  it  is  subjected  along  with  the  other 
abdominal  muscles.  The  inferior  part  of  its  tendon  is  incompletely  developed 
by  the  absence  of,  tbe  superficial  fibres  which  retain  together  the  more  deeply 
seated,  by  which  it  is  weakened  and  caused  to  gape  by  one  or  more  large  oblong 
fissures:  this  variety  gives  occasion  to  a  form  of  inguinal  hernia,  differing  mate- 
rially from  what  is  common. 


MUSCLES  OF  THE  ABDOMEN.  387 

muscle,  in  general,  decussate  the  fibres  of  the  external  oblique, 
all  of  them  do  not;  for  the  lower  are  brought  gradually  to  pur- 
sue the  same  direction  towards  the  symphysis  of  the  pubes. 

Near  the  Linea  Semilunaris,  the  muscular  fibres  cease,  and 
the  tendon  begins. 

It  is  inserted,  by  condensed  fibrous  cellular  membrane,  into 
the  cartilages  of  the  seventh,  eighth,  and  ninth  ribs;  and  by 
flesh  into  the  tenth,  eleventh,  and  twelfth.  It  is  inserted  also, 
membranous,  into  the  side  of  the  ensiform  cartilage,  its  whole 
length;  and  into  the  linea  alba,  from  the  sternum  to  the  pubes. 

The  tendon  of  this  muscle  divides  into  two  laminae,  which 
enclose  the  rectus  muscle,  and  thereby  form  a  sheath  for  it, 
imperfect,  however,  at  the  lower  posterior  part  near  the  pubes. 

Its  use  is  the  same  as  that  of  the  External  Oblique.* 


3.   The  Transversalis  Abdominis, 

Arises  from  the  transverse  processes  of  the  last  dorsal,  of  the 
four  upper  lumbar  vertebra,  and  from  the  back  part  of  the 
crista  of  the  ilium  by  the  Fascia  Lumborum.  It  also  arises, 
fleshy,  from  the  anterior  two-thirds  of  the  spine  of  the  ilium, 
and  from  the  exterior  half  of  Poupart's  ligament;  and  tendinous 
and  fleshy  alternately,  from  the  inferior  margin  of  the  thorax, 
formed  by  the  cartilages  of  the  six  or  seven  inferior  ribs,  at 
their  inner  surfaces,  where  they  are  concerned  in  the  origin  of 
the  diaphragm. 

The  fleshy  part  of  this  muscle  occupies  about  one-third  of 
its  extent.  It  is  inserted  into  the  side  of  the  ensiform  cartilage; 
filling  up  the  vacancy  between  it  and  the  cartilages  of  the  sixth 
and  seventh  ribs;  and  into  the  linea  alba,  from  the  extremity  of 
the  sternum  to  the  pubes.  The  Transversalis  and  the  Internal 
Oblique  also  form  below  a  common  tendon,  which  is  inserted 
for  an  inch  into  the  crista  of  the  pubes,  behind  the  insertion  of 
Gimbernat's  Ligament; — into  the  spine  of  the  pubes; — and  into 
that  part  of  the  body  of  the  pubes  which  forms  the  lower  pos- 
terior boundary  of  the  external  abdominal  ring.  Just  above 
this  insertion  the  common  tendon  alluded  to  splits  into  two  la- 

*  Varieties.  It  is  sometimes  defective  at  its  lower  part,  and  on  other  occa- 
sions redundant. 


388  MUSCLES. 


minae,  terminating  in  the  linea  alba;  one  of  which  goes  before 
and  the  other  behind  the  pyramidalis  muscle,  so  that  a  sheath 
is  thus  formed  for  it. 

Use;  to  compress  the  contents  of  the  abdomen.* 


4.  The  Rectus  Mdominis, 

Is  seen  beneath  the  tendons  of  the  other  muscles  on  either 
side  of  the  linea  alba.  Its  origin  is  by  a  flat  tendon  of  an  inch 
or  more  in  breadth  from  the  symphysis  pubis  and  the  upper 
posterior  part  of  the  body  of  the  pubes.  The  muscle  increases 
gradually  in  its  ascent  to  the  breadth  of  three  or  four  inches. 
The  tendinous  intersections,  confining  it  to  the  tendinous  sheath 
in  front,  are  fixed  at  the  places  mentioned  as  linese  trans  versa?; 
hut,  for  the  most  part,  they  do  not  extend  through  the  muscle. 
When  the  origins  of  the  Recti  are  examined  from  behind,  it 
will  be  seen  that  the  internal  edge  of  one  tendon,  just  above  the 
symphysis  pubis,  overlaps  the  corresponding  part  of  the  other; 
also,  that  a  small  pyramidal  ligament  finishes  more  completely 
the  structure  just  above  the  symphysis  pubis;  this  ligament  is 
called  by  M.  G.  Breschet,  the  Superior  Pubic. 

The  Rectus  is  inserted  fleshy  into  the  base  of  the  cartilago- 
ensiformis,  and  into  the  cartilages  of  the  fifth,  sixth,  and  se- 
venth ribs. 

It  draws  the  thorax  towards  the  abdomen.t 


5.   The  Pyramidalis, 

Is  at  the  lower  front  part  of  the  rectus,  and  is  about  three 
inches  long.  It  arises  somewhat  thick,  tendinous,  and  fleshy, 
from  the  upper  part  of  the  pubes,  from  near  its  spine  to  the  sym- 
physis, between  the  rectus  behind  and  the  insertion  of  the  ex- 

*  Varieties.  Sometimes  transverse  tendinous  fibres  creep  across  its  belly,  and 
on  other  occasions  a  small  transverse  muscle  is  present,  which  decussates  the 
larger,  and  is  inserted  into  the  twelfth  rib. 

f  Varieties.  If  there  are  eight  sternal  ribs,  then  this  muscle  has  an  additional 
costal  insertion.  It  sometimes  sends  a  fasciculus  to  the  fourth  rib;  and  I  have 
seen  it  ascending  over  the  pectoralis  major,  to  the  root  of  the  neck,  as  occurs  in 
mamraiferous  animals. 


MUSCLES  OF  THE  ABDOMEN.  389 

ternal  oblique  before.  Being  fixed  in  the  sheath  formed  by  the 
separation  of  the  tendon  of  the  transversalis  muscle  it  tapers  to 
a  point  above,  and  is  inserted  into  the  linea  alba  and  internal 
edge  of  the  rectus,  for  about  the  upper  two-thirds  of  its  own 
length. 

It  strengthens  the  lower  part  of  the  abdomen.* 
At  the  linea  semilunaris  the  tendon  of  the  internal  oblique 
and  of  the  transversalis  unite  intimately;  and  just  beyond  this 
junction  the  two  laminae  are  formed,  which  enclose  the  rectus 
muscle.  The  anterior  lamina  is  one  half  of  the  tendon  of  the 
internal  oblique,  which,  after  passing  half  an  inch  or  an  inch,  is 
joined  to  the  tendon  of  the  external  oblique,  goes  in  front  of  the 
rectus  muscle,  and  covers  it  from  origin  to  insertion.  The 
posterior  lamina,  made  by  the  posterior  half  of  the  tendon  of 
the  internal  oblique,  is  united  already  at  the  linea  semilunaris  to 
the  tendon  of  the  transversalis:  in  this  manner  they  pass  behind 
the  rectus  muscle  from  the  cartilago-ensiformis  to  a  line  half- 
way between  the  umbilicus  and  the  pubes.  From  this  line, 
downwards,  all  the  tendons  go  in  front  of  the  rectus  muscle. 

The  obliquus  externus  tendon  may  be  dissected  from  the 
common  tendon  of  the  others,  without  much  difficulty,  almost 
to  the  linea  alba.  The  term  insertion,  expresses,  very  imper- 
fectly, the  manner  in  which  the  tendons  of  these  broad  muscles 
all  terminate  in  the  linea  alba  from  the  thorax  to  the  pelvis. 
It  should  rather  be  said,  that  they  coalesce  there  by  a  general 
intertexture  of  their  fibres. 


The  Cremasler, 

Is  commonly  attributed  exclusively  to  the  internal  oblique, 
as  it  is  said  to  be  a  detachment  of  fibres  from  it;  but  it  is  also 
formed  by  fibres  from  the  lower  edge  of  the  transversalis  mus- 
cle. The  history  of  its  formation  is  as  follows:  in  the  descent 
of  the  testicle,  the  latter  has  to  pass  beneath  that  edge  of  the 
transversalis  and  of  the  internal  oblique  which  is  extended  from 
the  outer  portion  of  Poupart's  ligament,  to  the  spine  and  crista 

*  Varieties.  It  is  frequently  defective,  but  sometimes  two,  three,  or  even  four, 
are  seen  on  a  side.  When  defective,  the  rectus  or  obliquus  internus  is  better 
developed  than  usual. 

33* 


390  MUSCLES. 

of  the  pubes.  As  the  testicle  descends,  it  comes  in  contact 
with  a  fasciculus  of  these  fibres,  and  takes  it  along.  This  con- 
stitutes the  Cremaster  muscle,  which,  in  adult  life,  and  in  a 
strong  muscular  subject,  is  seen  descending  on  the  outside  of 
the  spermatic  chord,  and  spreading  over  the  anterior  part  of 
the  tunica  vaginalis  in  arches  with  their  convexities  down- 
wards, then  rising  on  the  inner  side  of  the  chord,  to  be  inserted 
into  the  spine  of  the  pubes.* 
It  draws  up  the  testicle. 


Fascia  Transversalis  Abdominis. 

The  Fascia  Transversalis  is  placed  immediately  behind  the 
transversus  muscle,  between  it  and  the  peritoneum.  An  open- 
ing in  it,  which  permits  the  spermatic  chord  to  pass,  is  called 
the  Internal  Abdominal  Ring,  in  order  to  distinguish  it  from  the 
opening  in  the  tendon  of  the  external  oblique,  called  the  Exter- 
nal Ring.  The  internal  ring  is  rather  nearer  to  the  symphysis 
pubis  than  to  the  spine  of  the  ilium.  The  space  between  the 
internal  ring  and  the  external  ring,  is  about  eighteen  lines  in 
the  adult,  and  is  very  properly  called  the  Abdominal  Canal, 
from  giving  passage  to  the  spermatic  chord.  The  anterior  side 
of  the  canal  is  formed  by  the  tendon  of  the  external  oblique;- 
the  inferior  part,  in  the  erect  posture,  is  formed  by  Gimbernat's 
ligament;  the  posterior  side  is  formed  by  the  fascia  trans versa- 
lis;  and  above,  this  canal  is  overhung  by  the  internal  oblique 
and  the  transversalis  muscles.  The  spermatic  chord,  after  pe- 

*  Anat.  De  L'Homme,  par  Jul.  Cloquet.  This  account,  though  easily  verified 
in  some  subjects,  and  especially  in  such  as  are  muscular,  does  not  appear  to  be 
applicable  to  all,  or,  in  other  words,  the  arrangement  in  them  is  not  quite  so  ob- 
vious. It  does  not  agree  with  Mr.  John  Hunter's  observations  on  the  descent  of 
the  testicle;  for  he  always  found,  while  the  latter  was  still  in  the  loins,  the  cre- 
master  running  towards  it.  Moreover,  in  the  buffalo  of  America,  a  testicle  of 
which  Dr.  R.  Harlan,  of  this  city,  was  obliging  enough  to  furnish  me  with  for 
dissection,  I  found  that  the  cremaster,  though  remarkably  robust  and  strong, 
forms  none  of  those  nooses  or  arches  with  their  convexities  downwards,  but  ter- 
minates at  the  testicle  in  a  tendinous  and  somewhat  abrupt  manner.  Taking  all 
these  points  into  consideration,  it  may  be,  that  a  part  of  the  cremaster  is  formed 
after  the  manner  indicated  by  Mr.  Hunter,  and  another  part  after  that  mentioned 
by  M..  Cloquet;  or,  indeed,  cases  may  occur,  presenting  exclusively  one  or  the 
other. 


MUSCLES  OF  THE  ABDOMEN.  39 1 

netrating  the  fascia  transversalis,  does  not  cross,  directly  at 
right  angles,  the  inferior  edge  of  the  internal  oblique  and  trans- 
versalis, but  it  slips  under  them  very  obliquely ;  its  inclination 
being  towards  the  pubes,  so  that  it  can  be  considered  as  disen- 
gaged from  the  inferior  edge  of  these  muscles,  only  about  the 
middle  of  the  abdominal  canal. 

The  opening  in  the  Fascia  Transversalis,  or  the  Internal 
Ring,  is  not  abrupt  and  well  defined;  but  the  fascia,  where  it 
transmits  the  spermatic  chord,,  is  reflected  by  a  thin  process, 
and  terminates  insensibly  in  its  cellular  substance.  At  the  pos- 
terior or  ventral  face  of  the  External  Ring,  the  fascia  transver- 
salis is  not  in  contact  with  the  cord;  but  that  part  of  the  ten- 
don of  the  internal  oblique  and  transversalis^which  is  inserted 
into  the  crista  of  the  pubes,  and  forms  a  sheath  for  the  pyrami- 
dalis  muscle,  is  placed  between  them,  and  secures  this  opening. 

The  peritoneum  covers  the  posterior  face  of  the  fascia  trans- 
versalis, and  is  thrown  into  a  duplicature  or  falciform  process, 
passing  from  near  the  middle  of  the  crural  arch  towards  the 
umbilicus.  This  duplicature  depends  upon  the  round  ligament 
of  the  bladder,  which  was  once  the  umbilical  artery  of  the  foe- 
tus. It  is  broader  near  the  pelvis  than  it  is  above,  has  its  loose 
edge  turned  towards  the  cavity  of  the  abdomen,  and  ascends 
near  the  pubic  margin  of  the  Internal  Ring.  The  effect  of  its 
existence  is  to  divide  the  posterior  face  of  the  inguinal  region 
into  two  shallow  fossae;  one  next  to  the  ilium,  and  the  other 
next  to  the  pubes.  The  one  next  to  the  ilium  contains  the  be- 
ginning of  the  internal  abdominal  ring,  which  is  frequently 
marked  by  a  little  pouch  of  peritoneum,  going  along  the  sper- 
matic chord  for  a  few  lines.  The  fossa  on  the  inner  or  pubic 
side  of  the  falciform  process  is  just  behind  the  external  ring, 
but  separated  from  it  by  the  fascia  transversalis,  along  with  the 
tendon  of  the  lower  part  of  the  internal  oblique  and  of  the 
transversalis  muscle,  where  it  is  inserted  into  the  pubes,  and 
forms  the  sheath  of  the  pyramidalis.  The  two  fossae  indicate 
the  points  where  inguinal  hernias  commence ;  the  proper  ingui- 
nal protrusion  begins  in  the  external  fossa,  and  the  ventro-in- 
guinal  sometimes  in  the  internal  fossa. 

The  view  of  the  fascia  transversalis  from  behind  is  extremely 
satisfactory.  For  a  proper  knowledge  of  this  membrane,  the 
profession  is  indebted  to  the  labours  of  Sir  Astley  Cooper ;  and 


392  MUSCLES. 

much  of  the  zeal  with  which  the  anatomy  of  hernia  has  been 
investigated,  in  latter  years,  is  attributable  to  him.  The  fascia 
transversalis  is  a  thin  tendinous  membrane,  most  generally;  oc- 
casionally it  is  merely  condensed  cellular  membrane.  It  arises 
from  the  internal  or  abdominal  edge  of  Pouparfs  ligament,  and 
from  the  crista  of  the  pubes  just  behind  the  insertion  of  the 
common  tendon  of  the  internal  oblique  and  transversalis  mus- 
cles, and  is  extended  upwards  on  the  posterior  face  of  the  trans- 
versalis muscle  to  the  thorax.  At  its  origin  it  is  attached  to  the 
inferior  edge  of  the  transversalis  and  internal  oblique,  particu- 
larly the  part  between  the  internal  ring  and  the  symphysis 
pubis.  It  is  also  attached  to  the  exterior  margin  of  the  rectus 
abdominis  where  it  is  deprived  behind  of  its  sheath.  The  in- 
ternal abdominal  ring,  or  opening  in  this  fascia,  marks  it  out 
in  some  measure  into  two  portions,  of  which  that  on  the  iliac 
side  of  the  ring  is  not  so  thick  as  the  other,  or  the  one  on  the 
pubic  side;  and  both  portions  are  much  more  tendinous  near 
the  crural  arch  than  they  are  higher  up. 

Were  it  not  for  the  important  influence  of  the  fascia  superfi- 
cialis  abdominis  and  the  fascia  transversalis  upon  hernia,  and 
the  consequent  necessity  of  a  minute  knowledge  of  them,  their 
description  might  be  much  curtailed  in  considering  them  in  their 
proper  light,  to  wit;  as  sheaths  of  the  abdominal  muscles;  for 
it  is  now  sufficiently  apparent  that  the  first  is  contiguous  to  the 
external  oblique,  and  the  second  to  the  transverse  muscle. 
Upon  the  same  principle,  fasciae  might  be  made  of  all  the  la- 
minae of  cellular  substance  intermediate  to  the  abdominal  mus- 
cles, but  it  would  be  useless,* 

*  A  very  elaborate  and  exact  account  of  the  construction  of  the  parts  concerned 
in  hernia  has  lately  been  presented  by  Alexander  Thomson,  M.  D.,  under  the 
title  of  Oiivrage  complet  sur  L'Anatomie  du  Bas  Ventre.  Paris,  1838.  The  cha- 
racter of  this  work  is  not  so  much  inventive  as  distinguished  by  great  minute- 
ness of  research,  and  a  different  distribution  of  the  matter  from  what  is  common* 
together  with  a  most  copious  supply  of  new  terms  in  place  of  old  ones.  Highly 
creditable  as  it  is  to  his  industry,  we  can  scarcely  do  less  than  protest  against 
the  latter  irregularity,  and  express  our  apprehensions  that  this  objection,  together 
with  the  unusual  approaches  which  he  has  opened  to  the  structure  as  a  substi- 
tute for  the  settled  ones,  will  restrict  very  much  the  reception  of  his  work,  and 
render  it  less  acceptable  to  both  teacher  and  student.  The  splitting  and  inven- 
tion of  fasciae  was  considered  for  some  time  as  almost  exclusively  an  Anglican 
malady;  it  appears,  also,  to  have  propagated  itself  to  Paris  in  an  exasperated 
form  in  this  production  of  Mr.  Thomson  and  in  that  of  Mr.  Velpeau,  (Anatomie 


MUSCLES  OF  THE  PARIETES  OF  THE  ABDOMEN.  "393 

i 

On  removing  the  peritoneum  from  the  iliacus  internus  mus- 
cle, the  spermatic  vessels  are  seen  to  descend  from  the  loins 
to  the  internal  ring,  where  they  are  joined  by  the  vas  deferens 
coming  from  the  pelvis.  As  they  engage  under  the  edge  of 
the  internal  oblique  muscle,  after  penetrating  the  ring,  the  cre- 
master  muscle  is  detached  to  spread  itself  over  them.  The 
spermatic  chord,  thus  constructed, passes  through  the  abdominal 
canal  in  the  manner  mentioned,  obliquely  downwards  and  in- 
wards; and,  emerging  from  the  external  ring,  it  descends  ver- 
tically, lying  rather  upon  the  outer  column  of  the  ring  than 
upon  its  base. 

On  the  posterior  face  of  the  fascia  transversalis,  between  it 
and  the  peritoneum,  is  the  Epigastric  Artery.  The  epigastric 
arises  from  the  external  iliac  as  the  latter  is  about  to  go  under 
the  crural  arch;  it  ascends  inwardly  along  the  internal  margin 
of  the  internal  abdominal  ring  to  the  exterior  margin  of  the 
rectus  abdominis  muscle,  which  it  reaches  after  a  course  of 
two  and  a  half  or  three  inches.  The  spermatic  chord,  in  get- 
ting from  the  abdomen  to  the  abdominal  canal,  therefore, 
winds,  in  part,  around  the  epigastric  artery;  in  the  first  of  its 
course  being  at  the  iliac  edge  of  the  artery,  and  then  in  front 
of  it.  Two  epigastric  veins  attend  the  artery,  one  on  each 
of  its  sides,  and  end  by  a  common  trunk  in  the  external  iliac 
vein. 

The  anatomical  arrangement  of  the  parts  concerned  in  in- 
guinal hernia  in  the  female  is  the  same  as  in  the  male,  except 

Chirurgicale,  3d  Edition,  1838,)  both,  unquestionably,  works  of  much  merit. 
The  practical  anatomist  may,  however,  ask,  if  all  of  the  laminae  described  as  such 
be  fasciee,  what  has  become  of  the  cellular  substance  which  formerly  entered  so 
largely  into  the  composition  of  the  human  body  ?  Will  he  not  rather  find  verbal 
novelties  than  new  existences?  A  sound  anatomical  verdict  is  yet  to  be  given  on 
these  points:  our  own  opinion  is,  that  anatomy  is  too  staid  a  science  for  mere 
caprices  in  description  and  names,  and  that  such  innovations  cannot  possibly  be- 
come oecumenical.  The  introduction  of  a  new  name  in  the  place  of  an  old  one 
is  the  highest  act  of  medical  authority,  and  is  so  seldom  sanctioned  by  general 
suffrage,  that  an  individual  inclining  to  it  may  well  pause,  lest,  in  so  doing,  he 
may  seal  up  his  own  publications,  by  the  use  of  terms  too  little  known  to  be  con- 
venient or  desirable. 


394  MUSCLES. 

that  the  round  ligament  of  the  uterus  supplies  the  place  of  the 
spermatic  chord,  and  there  is  no  cremaster  muscle.* 


SECT.  III. — MUSCLES  OF  THE  UPPER  AND  POSTERIOR  PARIETES  OF  THE 

ABDOMEN. 

These  muscles  are  constituted  by  a  single  symmetrical  one, 
and  by  four  pairs :  they  can  only  be  seen  advantageously  by 
removing  the  abdominal  viscera. 

1.  The  Diaphragm,  (Diaphragma,) 

Is  a  complete,  though  moveable  septum,  placed  between  the 
thoracic  and  abdominal  cavities;  it  is  extremely  concave  be- 
low and  convex  above,  the  concavity  being  occupied  by  seve- 
ral of  the  abdominal  viscera.  It  is  in  contact  above  with  the 
pericardium  and  lungs,  and  below  with  the  liver,  spleen,  and 
stomach. 

It  is  connected  with  the  inferior  margin  of  the  thorax  on  all 
sides,  and  has  for  its  centre  a  silvery  tendon,  resembling  in  its 
outline  the  heart  of  a  playing  card.  This  cordiform  tendon 
occupies  a  considerable  part  of  the  extent  of  the  diaphragm, 
has  its  apex  next  to  the  sternum,  and  its  notch  towards  the 
spine ;  and  the  muscular  part  of  the  diaphragm  is  inserted  all 
around  into  its  circumference.  The  cordiform  tendon  is  nearly 
horizontal  in  the  erect  posture,  its  elevation  being  on  a  line 
with  the  lowest  end  of  the  second  bone  of  the  sternum.  On 
each  side  of  this  tendon  some  of  the  muscular  fibres  rise  so  high 
upwards  before  they  join  it,  that  they  are  on  a  horizontal  level 
with  the  anterior  end  of  the  fourth  rib.  The  fasciculi  of  mus- 
cular fibres  are,  for  the  most  part,  convergent  from  the  cir- 
cumference of  the  thorax,  and  are  easily  separated  from  one 
another. 

In  the  diaphragm  are  three  remarkable  foramina.  The  first 
(the  Foramen  CEsophageum)  is  in  the  back  of  the  muscle,  be- 

*  For  an  account  of  both  Inguinal  and  Femoral  Hernia,  the  reader  is  referred 
to  Lessons  in  Practical  Anatomy,  2d  Edition.  Philadelphia,  1836. 


MUSCLES  OF  THE  PARIETES  OF  THE  ABDOMEN.         395 

tvveen  the  spine  and  the  notch  of  the  cordiform  tendon,  a  little 
to  the  left  of  the  middle  line.  It  gives  passage  to  the  oesophagus 
and  the  par  vagum  nerves  along  with  it,  and  is  rather  a  fissure 
or  a  long  elliptical  foramen  made  by  the  separation  and  reunion 
of  the  muscular  fibres;  for,  above  and  below,  at  each  end  of  the 
ellipsis,  these  fibres  decussate-  one  another  in  columns.  To  the 
right  of  this  foramen,  and  a  little  above  its  horizontal  level,  in 
the  back  part  of  the  cordiform  tendon,  is  a  very  large  and  pa- 
tulous  foramen  for  the  ascending  vena  cava,  (Foramen  Quad- 
ratum.)  Its  form  is  between  an  irregular  quadrilateral  figure 
and  a  circle ;  its  edges  are  composed  of  fasciculi  of  tendon 
rounded  off,  and  are  not  susceptible  of  displacement,  or  of  al- 
teration in  their  relative  position  to  each  other;  by  which  means 
is  obviated  any  impediment  which  might  arise  from  a  different 
arrangement,  to  the  course  of  the  blood  in  the  ascending  cava. 
Almost  in  a  vertical  line  below,  and  about  three  inches  from 
the  foramen  for  the  oesophagus,  is  the  third  hole,  in  the  dia- 
phragm, which  affords  passage  to  the  aorta,  (Hiatus  Aorticus.) 
It  is  just  in  front  of  the  bodies  of  the  three  upper  lumbar  verte- 
brae, and  is  a  much  longer  elliptical  hole  than  the  ossophageal; 
its  lowest  extremity  or  pole  is  constituted  by  the  tendinous 
crura  of  the  diaphragm,  and  its  upper  by  a  decussation  of  mus- 
cular fasciculi  arising  from  them.  Through  it,besides  the  aorta, 
pass  the  Thoracic  Duct,  and  the  Great  Splanchnic  Nerve  of 
both  sides. 

In  the  horizontal  position  of  either  the  dead  or  the  living 
body,  the  right  side  of  the  diaphragm  ascends  higher  in  the 
thorax  than  the  left ;  but  the  weight  of  the  liver  makes  it,  in 
the  vertical  posture,  descend  lower  than  the  other. 

Thus  circumstanced,  the  detailed  origin  of  the  Diaphragm  is 
as  follows :  It  arises  fleshy  from  the  internal  face  of  the  upper 
edge  of  the  Xiphoid  Cartilage,  from  the  internal  face  of  the  car- 
tilages of  the  seventh  true,  and  of  the  succeeding  false  ribs, 
on  each  side;  that  is,  from  the  cartilages  of  the  eighth  and  ninth, 
from  the  osseous  extremities  of  the  tenth  and  eleventh,  and  from 
both  the  osseous  and  cartilaginous  termination  of  the  twelfth 
rib.  As  the  line  described  includes  almost  the  whole  of  a 
circle,  and  the  fibres  all  converge  to  the  cordiform  tendon, 
they,  of  course,  will  pass  in  different  radiated  directions,  and 
be  of  different  lengths,  which  it  is  unnecessary  to  specify.  Be- 


396  MUSCLES. 

tween  the  sternal  and  costal  portion  on  each  side,  there  is  a 
triangular  fissure  filled  with  fatty  cellular  tissue,  which  some- 
times leaves  an  opening  for  hernia.  I  have  seen  a  case  of  the 
kind,  in  which  the  transverse  part  of  the  colon  was  the  subject 
of  protrusion  into  the  thorax.  It  is  probable  that  the  great  dis- 
placement of  the  abdominal  viscera  into  the  thorax,  which  some- 
times occurs,  may  have  a  congenital  origin  in  this  very  fissure, 
and  is  subsequently,  when  the  parts  are  accommodated  to  their 
unnatural  situation,  thought  to  be  a  lusus  naturae.  The  portion 
described  is  called  the  Greater  Muscle  of  the  Diaphragm. 

Besides  these  origins,  the  diaphragm  has  several  from  the 
vertebrae  of  the  loins,  constituting  its  crura;  there  being  four 
on  each  side  of  the  foramen  for  the  aorta.  The  first  pair,  en- 
tirely tendinous,  comes  from  the  front  of  the  body  of  the  third 
vertebra  of  the  loins,  and  is  prevented  from  being  very  distinct 
in  its  origin,  in  consequence  of  running  into  the  ligament  in  front 
of  the  bodies  of  all  the  vertebrae  or  the  Anterior  Vertebral  Li- 
gament as  it  is  called.  The  second  pair  of  heads  is  on  the  out- 
side of  the  first,  and  arises,  tendinous,  from  the  intervertebral  li- 
gament, between  the  second  and  third  vertebrae.  The  third  pair 
of  heads  arises  tendinous  from  the  upper  part  of  the  lateral  face 
of  the  second  lumbar  vertebra.  And  the  fourth  pair  of  heads 
comes  also  tendinous,  from  the  fore  part  of  the  root  of  the 
transverse  process  of  the  second  lumbar  vertebra.  These  ten- 
dinous heads  terminate  in  what  is  called  the  Lesser  Muscle  of 
the  Diaphragm,  which  is  inserted  into  the  notch  of  the  cordi- 
form  tendon.  It  will  now  be  understood  that  the  aorta  passes 
between  the  two  sides  of  the  lesser  muscle,  and  that  the  oeso- 
phagus has  a  hole  in  the  upper  part  of  its  belly.* 

The  origin  of  the  diaphragm  is  completed  between  its  great- 
er and  lesser  muscle,  by  a  tense  ligament,  the  Ligamentum  Ar- 
cuatum,  which  passes  from  the  root  of  the  transverse  process 
of  the  first  lumbar  vertebra  to  the  inferior  part  of  the  middle 

*  This  origin  of  the  lesser  muscle  of  the  diaphragm  is  given  by  Albinus,  but 
it  is  difficult  to  make  out  fairly;  for  the  most  part  it  would  be  much  more  correct 
to  say  that  it  arises  tendinous,  from  the  first,  second,  and  third  vertebrae  in  front, 
and  the  corresponding  intervertebral  matter.  The  heads  are  generally  much 
smaller  on  one  side,  the  left,  than  the  other.  From  which  cause  a  large  fascicu- 
lus of  muscle  passes  from  the  right  to  the  left  side  in  ascending,  and  separates 
the  hole  for  the  aorta,  from  that  for  the  oesophagus. 


MUSCLES  OF  THE  PARIETES  OF  THE  ABDOMEN.         397 

of  the  twelfth  rib ;  with  the  upper  edge  of  this  ligament  the 
diaphragm  is  connected;  and  with  the  lower,  the  psoas  mag- 
nus  muscle,  and  the  quadratus  lumborum.  At  the  margin  of 
the  other  ribs,  the  diaphragm  is  connected  with  the  transver- 
salis  abdominis. 

Use.  In  consequence  of  the  muscular  fibres  of  the  diaphragm 
passing  in  a  curved  direction  from  the  circumference  of  the 
thorax  to  the  cordiform  tendon;  and  of  those  fibres  forming  a 
body  concave  below  and  convex  above,  their  contraction  at 
the  same  moment  enlarges  the  cavity  of  the  thorax,  and  has  a 
tendency  to  diminish  that  of  the  abdomen,  which  latter  is  pre- 
vented by  the  yielding  of  the  abdominal  muscles.  In  easy  res- 
piration, its  contractions  and  relaxations  produce  alternately 
the  actions  of  inspiration  and  of  expiration.  Its  descent,  also, 
assists  in  the  expulsion  of  faecal  and  other  matters  from  the 
abdomen.  By  the  experiments  of  Bourdon,*  it  appears  that  it 
only  acts  a  secondary  part  in  the  latter, — that  its  functions  are 
limited  to  inspiration  and  the  associated  actions;  but  that  in 
regard  to  its  power  of  assisting  in  the  expulsion  of  the  contents 
of  the  abdomen,  all  that  it  does  is  first  of  all  to  fill  the  lungs 
with  air,  and  then  the  closure  of  the  glottis  prevents  the  air  from 
being  expelled  from  the  lungs.  Common  observation  in  partu- 
rition shows  us,  that  the  expulsive  effort  of  the  abdominal  mus- 
cles does  not  take  place  when  inspiration  is  going  on,  for  the 
former  would  prevent  the  latter;  but  the  moment  that  expira- 
tion begins,  it  is  arrested  by  the  firm  closure  of  the  glottis,  and 
then  the  abdominal  muscles  contract  advantageously. 

The  Quadratus  Lumborum, 

Is  an  oblong  muscle,  arising  from  the  crista  of  the  ilium,  at 
the  side  of  the  lumbar  vertebras,  by  a  tendinous  and  fleshy  ori- 
gin of  three  inches  in  length.  It  is  inserted  into  the  transverse 
process  of  each  of  the  lumbar  vertebrae  and  of  the  last  of  the 
back  by  a  short  tendinous  slip:  it  is  also  inserted  into  the  low- 
er edge  of  the  last  rib  near  its  head,  beneath  the  ligamentum 
arcuatum. 

It  bends  the  loins  to  one  side,  and  draws  down  the  last  rib. 

*  Recherches  sur  la  Respiration  et  la  Circulation.     Paris,  1820. 
VOL.  I.— 34 


398  MUSCLES. 


It  is?  covered  behind  by  the  tendinous  origin  of  the  transver- 
salis  abdominis,  which  separates  it  from  the  sacro-Iumbalis  and 
from  the  longissimus  dorsi.  It  may  also  be  seen  very  well 
from  behind,  in  the  dissection  of  the  back.* 


The  Psoas  Parvus, 

Arises,  fleshy,  from  the  contiguous  edge  of  the  body  of  the 
Jast  dorsal  and  of  the  first  lumbar  vertebra  at  their  sides,  and 
from  the  intervertebral  ligament.  It  is  at  the  anterior  and  in- 
ternal edge  of  the  psoas  magnus;  has  a  short  belly,  and  a  long 
tendon  by  which  it  is  inserted  into  the  linea  innominata,  about 
half-way  between  the  spine  of  the  pubes  and  the  junction  of 
this  bone  with  the  ilium.  The  tendon,  besides,  is  expanded  into 
the  fascia  iliaca. 

Its  use  seems  to  be,  to  draw  upwards  the  sheath  of  the  fe- 
moral vessels,  which  is  derived  from  the  fascia  iliaca,  and,  con- 
sequently, to  draw  upwards  the  vessels  themselves;  which  pro- 
bably diminishes  the  liability  to  injury  from  their  too  great  or 
sudden  flexion.  This  muscle  is  sometimes  wanting. 

The  Psoas  Magnus. 

Arises,  fleshy,  from  the  side  of  the  body  of  the  last  dorsal 
and  of  the  four  upper  lumbar  vertebrae,  and  from  the  transverse 
processes  of  all  the  lumbar  vertebrae.  It  forms  an  oblong  fleshy 
cushion  on  the  side  of  the  lumbar  vertebrae,  and  constituting  the 
lateral  boundary  of  the  inlet  to  the  pelvis,  it  passes  out  of  the 
pelvis,  under  Poupart's  ligament,  about  its  middle. 

It  is  inserted  tendinous,  into  the  trochanter  minor  of  the  os 
femoris,  and  fleshy  for  an  inch  below  it. 

It  bends  the  body  forwards,  or  draws  the  thigh  upwards.f 

*  Varieties.  Sometimes  a  broad  tendon  from  it  is  inserted  into  the  inferior 
margin  of  the  body  of  the  eleventh  vertebra  of  the  back.  Sometimes  a  fascicu- 
lus of  it  touches  the  margin  of  the  eleventh  rib,  near  its  head,  and  above  the  in- 
tercostal vessels. 

•j-  Varieties.  Sometimes  it  is  joined  by  muscular  fasciculi  from  the  first,  se- 
cond, and  even  the  third  bone  of  the  sacrum.  Sometimes,  where  it  borders  on 
the  pelvis,  there  is  a  small  fasciculus,  which  continues  distinct  almost  to  the  tro- 
chanter minor,  and  then  sends  its  own  tendon  into  the  common  tendon  of  the 
iliacus  interims  and  psoas  magnus. 


MUSCLES  OF  THE  PARIETES  OF  THE  ABDOMEN.         399 


The  Iliacus  Intern  us, 

Occupies  the  concavity  of  the  ilium,  being  on  the  outside  of 
the  psoas  magnus.  It  arises,  fleshy,  from  the  transverse  pro- 
cess of  the  last  lumbar  vertebra;  from  the  internal  margin  of  the 
crista  of  the  ilium;  from  the  whole  concavity  of  the  latter;  from 
its  anterior  edge  at  and  above  the  anterior  inferior  spinous  pro- 
cess; and  from  that  part  of  the  capsule  of  the  hip  joint  near  the 
latter  process. 

This  muscle  terminates  in  the  tendon  of  the  psoas  magnus, 
just  above  its  insertion  into  the  trochanter  minor. 

This  and  the  psoas  magnus,  from  having  a  common  tendon, 
might  with  propriety  be  considered  as  only  one  muscle.  Their 
action  is  the  same,* 

Of  the  Fascia  Iliaca. 

The  Fascia  Iliaca  is  a  tendinous  membrane,  which  lies  on  the 
iliacus  internus  and  psoas  magnus  muscles,  and'  is  continued 
into  the  tendon  of  the  Psoas  Parvus.  Externally,  it  is  connect- 
ed to  the  margin  of  the  crista  of  the  ilium;  at  the  internal  edge 
of  the  psoas  magnus,  it  is  connected  with  the  brim  of  the  pel- 
vis, and  sinks  into  the  cavity  of  the  pelvis,  being  continuous 
with  the  Aponeurosis  Pelvica;  and  below,  it  is  inserted  into  the 
edge  of  the  crural  arch,  from  the  anterior  superior  spinous  pro- 
cess of  the  ilium  almost  to  the  pubes,  and  is  there  continuous 
with  the  fascia  transversalis  abdorninis.  The  external  iliac  ves- 
sels are  upon  this  fascia,  between  it  and  tho  peritoneum;  and 
below  them  the  fascia  iliaca  goes  over  that  part  of  the  pubes 
which  gives  origin  to  the  pectineus  muscle,  and  is  continuous 
with  the  pectineal  fascia,  or  that  which  covers  the  pectinqus 
muscle.  By  introducing  the  finger  or  a  knife  handle  into  a 
cut  through  the  fascia  iliaca,  its  attachment  to  the  crural  arch, 
and  its  continuity  with  the  fascia  pectinea  will  be  rendered  very 
obvious. 

*  Varieties.  Sometimes  an  additional  fasciculus  arises  below  the  inferior  an- 
terior spinous  process,  and  descends  along  the  external  margin  of  this  muscle. 
This  fasciculus  varies  somewhat  in  its  size  at  different  points,  and  is  inserted  into 
the  linea  aspera  below  the  trochanter  minor.  In  very  rare  cases,  the  iliacus  in- 
ternus is  kept  totally  distinct  from  the  psoas  magnus,  from  origin  to  insertion. 


400  MUSCLES. 

The  iliac  vessels  pass  beneath  the  crural  arch  on  the  inner 
margin  of  the  psoas  magnus  muscle,  the  vein  being  nearest  the 
pubes  and  the  artery  at  the  outer  side  of  the  vein.  The  fascia 
iliaca  being  inserted  into  the  crural  arch  as  far  as  the  vein,  may 
indeed  be  traced  to. the  crista  of  the  pubes;  it  is  so  connected 
with  the  vessels  that  no  opening  for  hernia  exists  between  them, 
or  indeed  in  all  the  space  from  the  internal  margin  of  the"  vein 
to  the  spine  of  the  ilium.  But  at  the  inner  side  of  the  vein, 
between  it  and  Gimbernat's  ligament,  an  opening  appears, 
called  the  Crural  or  Femoral  Ring,  and  is  the  place  where  fe- 
moral hernia  commences,  This  opening  is  generally  occupied 
by  a  lymphatic  gland,  and  a  lamina  of  condensed  but  loosely 
attached  cellular  substance,  continuous  with  the  Aponeurosis 
Pelvica. 


SECT.  IV. MUSCLES  ON  THE  POSTERIOR  FACE  OF  THE  TRUNK. 

The  Trapezius  or  Cucullaris, 

Is  a  beautiful  broad  muscle,  immediately  under  the  skin,  co- 
vering the  back  parts  of  the  neck  and  thorax,  and  extending 
from  the  bottom  of  the  latter  to  the  top  of  the  former.  Its  an- 
terior edge,  above,  is  parallel  with  the  posterior  edge  of  the 
sterno-cleido-mastoideus.  Its  posterior  edge  is  joined  with 
that  of  its  fellow,  and  below,  it  overlaps  in  part  the  latissimus 
dorsi. 

It  arises  from  the  occipital  protuberance,  and  from  eight  or 
ten  lines,  sometimes  more  of  the  superior  semicircular  ridge  of 
the  occiput,  by  a  tendinous  membrane.  It  arises  also  from  the 
five  superior  spinous  processes  of  the  neck  through  the  inter- 
vention of  the  ligamentum  nucha?,  and  tendinous  directly  from 
the  two  lower  spinous  processes  of  the  neck,  and  from  all  of 
the  back. 

It  is  inserted  fleshy  into  the  external  third  of  the  clavicle, 
tendinous  and  fleshy  into  the  inner  edge  of  the  acromion  pro- 
cess, and  into  all  the  spine  of  the  scapula.  Its  fibres  having  a 
very  extended  origin,  must  of  course  converge  in  getting  to. 


MUSCLES  OF  THE  BACK.  401 

these  insertions;  the  upper  fibres  descend,  the  lower  ascend, 
and  the  middle  are  horizontal.* 
It  draws  the  scapula  towards  the  spine. 

In  the  cervical  portion  of  these  muscles,  formed  by  the  ori- 
gins of  both  united,  is  an  elliptical  expanse  of  tendon,  lying  over 
the  ligamentum  nuchse,  and  extended  on  each  side.  The  liga- 
mentum  nuchse  itself,  as  mentioned  elsewhere,  is  a  vertical 
septum  of  ligamentous  matter,  extending  from  the  central  line. 
of  the  occipital  bone,  to  the  spinous  processes  of  all  the  verte- 
bras of  the  neck.  At  its  upper  part,  where  the  spinous  pro- 
cesses of  the  neck  are  short,  this  septum  is  very  broad,  and  di- 
vides completely  the  muscles  of  the  two  sides  of  the  neck. 


The  Latissimus  Dorsi, 

Is  situated  under  the  skin  at  the  lower  part  of  the  back,  so 
as  to  cover  the  whole  posterior  portion  of  the  latter.  It  arises 
by  a  thin  tendinous  membrane,  from  the  seven  inferior  spinous 
processes  of  the  back ;  and  by  a  thick  tendinous  membrane  from 
all  those  of  the  loins  and  sacrum.  Its  origin  also  extends  along 
the  outer  inferior  margin  of  the  sacrum,  and  from  the  posterior 
third  of  the  spine  of  the  ilium.t  Besides  which,  the  latissimus 
dorsi  has  from  the  sides  of  the  three  or  four  inferior  false  ribs, 
as  many  fleshy  heads  which  are  connected  with  the  inferior 
heads  of  the  obliquus  externus  abdominis. 

From  this  extended  origin  the  fibres  converge,  so  as  to  form 
the  posterior  fold  of  the  axilla;  and  to  terminate  in  a  flat,  thick 
tendon,  of  two  inches  in  breadth,  which  is  inserted  into  the 
posterior  ridge  of  the  bicipital  groove  of  the  os  humeri.  The 
upper  part  of  tins  muscle  passes  over  the  inferior  angle  of  the 
scapula,  and  derives  a  fasciculus  of  fibres  from  it.  It  is  there 
behind  the  teres  major,  but  as  it  advances  it  winds  around  the 
inferior  edge  of  the  latter  so  as  to  get  before  it.  Afterwards 

*  Varieties.  It  is  sometimes  short  of  the  origin  described,  by  from  one  to 
four,  of  the  lower  spinous  processes  of  the  back.  Also  the  lower  fasciculus  is 
sometimes  disjoined  from  the  rest  of  the  muscle,  by  a  large  triangular  space. 

j-  This  origin  frequently  is  tendinous  at  the  back  part  of  the  ilium,  and  fleshy 
in  front. 

34* 


MUSCLES. 


the  tendons  of  the  two  adhere  closely,  but  have  a  bursa  between* 
them  at  their  termination.  That  portion  of  the  tendon  of  the 
latissimus  which  is  continuous  with  the  lower  edge  of  its  fleshy 
belly,  by  a  half  spiral  turn  in  the  latter,  becomes  uppermost  ; 
while  the  upper  portion  is  by  the  same  arrangement  made 
lowest.  At  the  place  of  its  insertion,  it  is  commonly  connected 
to  the  pectoralis*  major.  The  inferior  margin  of  its  tendon  de- 
taches a  slip  to  the  brachial  fas<?ia,  and  the  superior  margin 
another  to  the  smaller  tuberosity  of  the  os  humeri. 
It  draws  the  os  humeri  downwards  and  backwards.* 
The  thick  tendinous  membrane  coming  from  the  spinous  pro- 
cesses of  the  loins  and  back  is  the  fascia  lumborum,  and  is  com- 
mon to  the  latissimus  the  internal  and  external  oblique  muscles 
of  the  abdomen,  and  several  other  muscles  to  be  mentioned. 


The  Serratus  Inferior  Posticus. 

The  origin  of  this  muscle  is  inseparably  united  to  that  of  the 
latissimus  dorsi  by  the  fascia  lumborum,  and  comes  from  the 
two  inferior  spinous  processes  of  the  back.,  and.the  three  superior 
of  the  loins. 

It  is  inserted  by  fleshy  digitalions  into  the  under  edge  of  the 
four  inferior  ribs. 

It  draws  the  ribs  downwards,  and  is  an  antagonist  to  the  dia- 
phragm in  some  respects,  but  more  particularly  to  the  serralus 
superior  posticus. 

The  removal  of  the  trapezius  brings  into  view  several  mus- 
•  :les;  the  most  superficial  of  which  are  the  rhomboid,  which, 
being  two  together,  look  very  much  like  one. 

*  Varieties.  Sometimes. from  its  anterior  extremity  a  fleshy  or  tendinous  slip 
is  detached  in  front  of  the  coraco-brachialis,  and  is  inserted  into  the  posterior 
face  of  the  tendon  of  the  pectoralis  major.  The  brachial  vessels  and  nerves  are 
liable  to  compression  from  this  arrangement,  which  is  said  to  be  natural  to'birds 
and  moles.  Another  variety  is  where  a  slip  runs  from  this  muscle,  adheres  to 
the  coraco-brachialis,  and  is  inserted  tendinous  into  the  coracoid  process  .of  the, 
scapula. 


MUSCLES  OF  THE  BACK.  403 

v 

The  Rhomboideus  Minor, 

Is  above  the  other.  It  is  a  narrow  muscle  which  arises  by 
a  thin  tendon  from  the  three  inferior  spinous  processes  of  the 
neck,  and,  passing  obliquely  downwards,  is  inserted  into  the 
base  of  the  scapula  opposite  the  beginning  of  its  spine. 

The  Rhomboideus  Major, 

Arises,  also,  by  a  thin  tendon  from  the  last  spinous  process  of 
the  neck,  and  from  the  four  superior  of  the  back,  and  is  insert- 
ed into  all  the  base  of  the  scapula  below  its  spine. 

These  muscles  draw  the  scapula  upwards  and  backwards. 

The  Serratus  Superior  Posticus, 

Arises  by  a  thin  tendon  from  the  three  inferior  spinous  pro- 
cesses of  the  neck,  and  the  two  superior  of  the  back,  and  is  in- 
serted into  the  second,  third,  fourth,  and  fifth  ribs,  by  tendi- 
nous and  fleshy  slips,  a  little  beyond  their  angles. 

This  muscle  draws  the  ribs  upwards. 

Between  the  two  serrati  is  an  aponeurotic  expansion  de- 
scribed by  Rosenmuller,.  which  connects  thenl  with  each  other, 
and  has  induced  some  anatomists  to  consider  them  as  but  one 
muscle.  It  is  thin  and  diaphanous,  but  has  the  fibrous  structure 
very  apparent,  and  running  in  a  transverse  direction  from  the 
spinous  processes  to  the  angles  of  the  ribs.  The  superior  mar- 
gin of  the  latissimus  dorsi  also  runs  into  this  fascia,  so  as  to 
render  its  own  bounds  somewhat  undefined.  This  fascia,  along 
with  the  ribs  and  vertebrae,  forms  that  canal  in  which  are  con- 
tained the  deep-seated  muscles  of  the  back. 


The  Levator  Scapulce, 

Is  placed  between  the  posterior  edge  of  the  sterno-cleido- 
mastoideus  and  the  anterior  of  the  trapezius ;  its  lower  end  is 
just  above  the  rhomboideus  minor.  It  arises  by  rounded  tea- 


404  MUSCLES. 

dons  from  the  three,  four,  or  five,  superior  transverse  processes 
of  the  neck,  between  the  scaleni  muscles  and  the  splenius  colli. 
It  is  inserted,  fleshy,  into  that  part  of  the  base  of  the  scapula 
above  the  origin  of  its  spine.  As  its  name  expresses,  it  draws 
the  scapula  upwards.  A  good  view  of  this  muscle  may  be  ob- 
tained in  the  front  dissection  of  the  neck.* 


The  Splenius, 

Has  its  inferior  extremity  beneath  the  serratus  superior  pos- 
ticus,  but  the  principal  part  of  it  is  covered  by  the  trapezius. 
It  arises  from  the  spinous  processes  of  the  five  inferior  cervical, 
and  of  the  four  superior  dorsal  vertebrae. 

It  is  inserted  into  the  back  of  the  mastoid  process  and  into  a 
small  part  of  the  adjacent  portion  of  the  os  occipitis,  also  into 
the  transverse  processes  of  the  two  superior  cervical  vertebras. 
It  is  customary  to  consider)-  the  part  which  goes  to  the  head  as 
Splenius  Capitis,  and  the  part  below  as  Splenius  Colli:  the  lat- 
ter, in  that  case,  is  said  to  arise  from  the  third  and  fourth  dor- 
sal vertebrae.  It  draws  the  head  and  neck  backwards. 

Between  the  spinous  processes  of  the  vertebras  and  the  angles 
of  the  ribs,  on  either  side,  the  deep  fossa  is  filled  up  entirely  by 
muscles.  Some  of  them  are  large  and  powerful,  and  the  most 
striking  are  the  Sacro-Lumbalis  and  the  Longissimus  Dorsi. 


The  Sacro-Lumbalis  and  Longisnimus  Dorsi, 

Have  a  common  origin  from  the  back  of  the  pelvis  and  of  the 
lumbar  vertebrae,  and  extend  to  the  top  of  the  thorax.  They 
arise,  tendinous  posteriorly,  and  fleshy,  anteriorly,  from  the  pos- 
terior surface  of  the  sacrum  by  its  external  margin  and  spinous 
processes:  they  arise,  also,  tendinous,  from  the  spinous  processes, 
and  fleshy,  from  the  ends  of  the  transverse  processes  of  all  the 

*  Varieties.  Sometimes  it  arises  from  only  two  superior  transverse  processes; 
occasionally  its  fasciculi  are  separated  from  the  neck  to  the  scapula;  or,  a  long  one 
is  detached  towards  the  spine,  thereby  presenting  a  disposition  similar  to  what 
is  met  with  in  the  dolphin. 

f  Albinus,  loc.  cit. 


MUSCLES  OF  THE  BACK.  405 

vertebrae  of  the  loins;  and  principally  tendinous  from  the  pos- 
terior part  of  the  spine  of  the  ilium.  The  external  margin  of  the 
belly  is  fleshy,  and  all  the  part  nearest  to  the  spine  is  wholly 
tendinous  below;  but,  higher  up  in  the  loins,  it  is  so  only  on  the 
surface.  The  tendon  is  very  strong,  and  divided  into  fasciculi, 
chiefly  near  the  spinous  processes  of  the  lumbar  vertebrae. 
From  the  under  surface  of  this  common  belly,  two  heads,  ten- 
dinous and  fleshy,  are  inserted  into  the  inferior  edge  of  the 
transverse  process  of  each  lumbar  vertebra,  the  smaller  near  its 
root,  and  the  larger  near  its  extremity.  On  a  level  with  the 
lower  rib,  and,  indeed,  somewhat  below  it,  a  fissure  occurs  in 
the  muscle  which  divides  it  into  two  parts. 

The  Longissirnus  Dorsi  is  nearest  the  spine;  it  is  inserted,  by 
small  double  tendons,  proceeding  from  its  internal  surface,  into 
the  ends  of  the  transverse  processes  of  all  the  vertebrae  of  the 
back,  except  the  first.  It  also,  from  its  outer  edge,  sends  long 
slender  tendons,  by  which  it  is  inserted  into  the  under  edges  of 
all  the  ribs  beyond  their  tubercles,  except  the  two  inferior. 

The  Sacro-Lumbalis  is  inserted  from  its  outer  edge  into  all 
the  ribs  at  their  angles,  by  long  and  thin  tendons,  which  are 
successively  longer,  the  higher  they  are  inserted. 

By  turning  over  this  muscle  towards  the  ribs,  from  the  other, 
one  may  see  coming  from  the  eight  lower  ribs,  as  many  slips, 
which  run  into  the  under  surface  of  the  sacro-lumbalis ;  they 
are  the  Musculi  Accessorii  ad  Sacro-Lumbalem. 

These  two  muscles  keep  the  spine  erect,  and  draw  down  the 
ribs.* 


Tile  Spinalis  Dorsi> 

Between  the  ends  of  the  spinous  processes  and  the  edge  of 
the  longissimus  dorsi,  is  a  muscle  almost  entirely  tendinous,  and 
scarcely  to  be  distinguished  from  the  latter,  both  in  consequence 

*  Varieties.  The  origin  is  uniform,  but  the  insertions  vary  in  their  number. 
Sometimes,  a  fasciculus  commences  by  a  tendinous  beginning  from  the  fourth 
rib,  and  is  inserted  into  the  transverse  process  of  the  sixth  vertebra  of  the  neck; 
a  fasciculus  from  the  sacro-lumbalis  joins  the  fascia  extended  between  the  two 
serrati,  or  reaches  to  the  spleniuscolli:  the  two  muscles  are  sometimes  joined 
closely  by  an  intermediate  fasciculus. 


406  MUSCLES. 

of  its  close  connexion  with  it,  and  of  its  insignificant  size.  At 
its  lower  part,  it  is  absolutely  a  portion  of  the  longissimus,  and 
can  be  separated  from  it  only  by  a  forced  division.  It  is  a  mere 
string  lying  along  the  sides  of  the  spinous  processes,  and  is  called, 
from  its  origin  and  insertion,  the  Spinalis  Dorsi. 

It  arises  tendinous  from  the  spinous  processes  of  the  two  supe- 
rior lumbar,  and  of  the  three  inferior  dorsal  vertebrae,  and  is  in- 
serted, tendinous,  into  tho  spinous  processes  of  the  nine  superior 
dorsal  vertebrae,  except  the  first. 

It  tends  to  keep  the  spine  erect. 


The  Cervicalis  Descendens, 

Is  a  small  muscle  placed  at  the  upper  portion  of  the  thorax, 
between  the  insertions  of  the  sacro-lumbalis,  and  of  the  longis- 
simus dorsi  into  the  upper  ribs;  it  looks,  at  first,  very  much 
like  a  continuation  or  appendix  of  the  first,  running  to  the  cer- 
vical vertebra?. 

This  muscle  arises  from  the  upper  edges  of  the  four  superior 
ribs  by  long  tendons:  it  forms  a  small  belly,  which  is  inserted 
by  three  distinct  tendons  into  the  transverse  processes  of  the 
fourth,  fifth,  and  sixth  vertebrae  of  the  neck,  between  the  leva- 
tor  scapulae  and  splenius  colli. 

It  draws  the  neck  backwards. 


The  Transversalis  Cervicis, 

Is  on  the  inner  side  of  the  last,  and  in  contact  with  it,  being 
about  the  same  size,  and  having  very  much  the  same  course 
and  appearance.  It  is  considered  as  an  appendage  to  the  lon- 
gissimus dorsi. 

It  arises  from  the  transverse  processes  of  the  five  superior 
dorsal  vertebrae  by  distinct  tendons,  and  forms  a  narrow  fleshy 
belly,  which  is  inserted  by  distinct  tendons,  also,  in  the  trans- 
verse processes  of  the  five  middle  cervical  vertebrae. 

It  draws  the  head  backwards. 


MUSCLES  OF  THE  BACK.  407 

The  Trachelo-Mastoideus, 

Is  at  the  inner  side  of  the  last  muscle,  in  contact  with  it. 

It  arises  by  distinct  tendinous  heads,  from  the  transverse 
processes  of  the  three  superior  vertebrae  of  the  back,  and  of  the 
five  inferior  of  the  neck ;  and  is  inserted,  by  a  thin  tendon,  into 
the  posterior  edge  of  the  mastoid  process. 

The  dorsal  origins  are  frequently  deficient  or  irregular. 

It  draws  the  head  backwards. 

The  Complexus, 

A  fine  large  muscle,  is  situated  at  the  inner  face  of  the  tra- 
chelo-mastoideus,  and  is  readily  recognised  by  showing  itself 
between  the  bellies  of  the  two  splenii  capitis,  just  below  the 
occiput.  A  quantity  of  tendinous  matter  exists  in  its  middle, 
which  gives  it  the  complicated  appearance  from  whence  its 
name  is  derived. 

It  arises,  by  tendinous  heads,  from  the  seven  superior  dorsal, 
and  the  four  inferior  cervical  vertebrae,  by  their  transverse  pro- 
cesses; also,  by  a  fleshy  slip  from  the  spinous  process  of  the 
first  dorsal.  It  is  inserted  into  the  inferior  part  of  the  os  occi- 
pitis,  by  the  surface  between  the  upper  and  lower  semicircular 
ridges,  on  the  outside  of  the  vertical  ridge  which  exists  in  the 
middle  of  the  bone. 

It  draws  the  head  backwards. 


The  Semi- spinatis  Cervicis, 

Is  a  muscle  which  passes  obliquely  from  transverse  to  spi- 
nous processes,  and  is  situated  between  the  complexus  and  the 
multifidus  spinae;  the  course  of  its  fibres  renders  it  difficult  to 
be  distinguished  from  the  latter. 

It  arises  from  the  transverse  processes  of  the  six  upper  ver- 
tebrae of  the  back,  by  tendons  which  adhere  to  those  of  the  ad- 
jacent muscles;  and  passes  up  to  the  neck,  to  be  inserted  into 
the  sides  of  the  spinous  processes  of  the  five  middle  cervical 
vertebrae. 

It  extends  the  neck  obliquely  backwards. 


408  MUSCLES. 

The  Semi-spinalis  Dorsi, 

Is  lower  down  on  the  spine,  and  with  difficulty  distinguished 
from  the  multifidus:  like  the  last,  it  passes  from  transverse  to 
spinous  processes.  It  lies  under  the  longissimus  dorsi,  between 
it  and  the  multifidus. 

This  muscle  arises  by  tendons  connected  with  those  of  the 
other  muscles,  from  the  transverse  processes  of  the  seventh, 
eighth,  ninth,  and  tenth  dorsal  vertebra?;  and  passes  upwards 
obliquely,  to  be  inserted,  tendinous,  into  the  sides  of  the  spinous 
processes  of  the  two  lower  cervical,  and  of  the  five  upper  dor- 
sal vertebras. 

It  draws  the  spine  obliquely  backwards. 


The  Multifidus  Spines, 

Lies  under  the  muscles  as  yet  mentioned,  close  to  the  bones 
of  the  spine;  in  order  to  see  it  well,  they,  therefore,  should  all 
be  cut  away. 

It  has  its  commencement,  tendinous  and  fleshy,  on  the  back 
of  the  sacrum,  being  connected  to  its  spinous  processes  and 
posterior  surface,  also  to  the  back  part  of  the  spine  of  the  ilium. 
It  there  forms  a  belly,  of  sufficient  magnitude  to  fill  up  much 
of  the  cavity  between  the  spinous  processes  of  the  sacrum  and 
the  posterior  part  of  the  ilium.  It  arises  also  from  the  roots  of 
the  oblique  and  transverse  processes  of  all  the  vertebra?  of  the 
loins,  of  the  back,  and  of  the  four  inferior  of  the  neck. 

The  multifidus  is  inserted,  tendinous  and  fleshy,  into  the  roots 
and  sides  of  the  spinous  processes  of  all  the  vertebrcc  of  the 
loins,  of  the  back,  and  of  the  five  inferior  of  the  neck. 

This  muscle  consists  of  a  great  number  of  small  bellies, 
which  are  parallel  to  each  other,  and  each  of  which  arises 
from  a  transverse  or  oblique  process,  and  goes  to  the  spinous 
process  either  of  the  first  or  second  vertebra  above  it. 

It  twists  the  spine  backwards,  and  keeps  it  erect. 

Between  the  head  and  the  first  and  second  vertebra),  and  be- 
tween the  two  latter,  there  are  on  either  side  four  small  mus- 


MUSCLES  OF  THE  BACK.  409 

cles,  intended  for  the  motion  of  these  parts  upon  each  other. 
They  are  brought  into  view  by  the  removal  of  the  complexus. 


The  Rectus  Capitis  Posticus  Major, 

Arises,  tendinous  and  fleshy,  from  the  extremity  of  the  spi- 
nous  process  of  the  dentata,  and  is  inserted  into  the  inferior 
transverse  or  semicircular  ridge  of  the  os  occipitis,  and  into  a 
part  of  the  continuous  surface  of  bone  below  it. 

Its  shape  is  pyramidal,  the  apex  being  below.  It  turns  the 
head,  and  also  draws  it  backwards. 


The  Rectus  Capitis  Posticus  Minor, 

Is  at  the  internal  edge  of  the  first.  It  arises,  tendinous,  from 
the  tubercle  on  the  back  part  of  the  first  vertebra,  and  is  in- 
serted into  the  internal  end  of  the  inferior  transverse  or  semi- 
circular ridge  of  the  os  occipitis,  and  into  a  part  of  the  surface 
between  it  and  the  foramen  magnum. 

It  is  also  pyramidal,  with  the  apex  downwards.  It  draws 
the  head  backwards. 


The  Obliquus  Capitis  Superior, 

Arises  from  the  transverse  process  of  the  first  cervical  ver- 
tebra, and  is  inserted  into  the  outer  end  of  the  inferior  semicir- 
cular ridge  of  the  os  occipitis,  behind  the  posterior  part  of  the 
mastoid  process,  and  beneath  the  splenius  muscle. 

It  draws  the  head  backwards. 


The  Obliquus  Capitis  Inferior, 

Arises  from  the  side  of  the  spinous  process  of  the  dentata, 
and  is  inserted  into  the  back  part  of  the  transverse  process  of 
the  first  vertebra  of  the  neck. 

It  rotates  the  first  vertebra  on  the  second. 

VOL.  L— 35 


410  MUSCLES. 

The  Inter-spinales, 

Are  small  short  muscles,  placed  between  the  spinous  pro- 
cesses of  contiguous  vertebrae.  In  the  neck  they  are  double, 
in  consequence  of  its  spinous  processes  being  bifurcated;  in  the 
back  they  are  almost  entirely  tendinous ;  in  the  loins  they  are 
single  and  well  marked. 

They  draw  the  spinous  processes  together,  and  keep  the 
spine  erect. 

The  Inler-transversarii, 

Are  also  short  muscles,  placed  in  a  similar  manner,  between 
the  transverse  processes  of  the  vertebra?.  In  the  neck  they 
are  double,  in  the  back  they  are  small,  tendinous,  and  not  well 
marked ;  and  in  the  loins  they  are  single  and  well  seen. 

They  draw  the  transverse  processes  together,  and  will,  of 
course,  bend  the  spine  to  one  side. 

The  Levatores  Costarum, 

Are  small  muscles  concealed  by  the  sacro-lumbalis  and  lon- 
gissimus  dorsi,  and  pass  from  the  transverse  process  of  the  last 
cervical  and  of  the  eleven  superior  dorsal  vertebrae,  to  the  up- 
per edges  of  the  next  ribs.  They  are  twelve  on  either  side  of 
the  spine,  are  tendinous  in  their  origins  and  insertions,  with  in- 
termediate muscular  bellies. 

The  upper  ones  are  small  and  thin.  They  increase  in  mag- 
nitude as  they  descend.  From  the  inferior  edge  of  nearly  all 
these  muscles  a  fleshy  slip  is  detached,  which  passes  over  the 
rib  next  below  its  origin,  to  the  second  rib  below,  and  occa- 
sionally to  the  third.  These  slips  are  called  Levatores  Costa- 
rum  Longiores.  The  others,  which  descend  from  the  trans- 
verse process  to  the  rib  next  below,  are  called  Levatores  Cos- 
tarum Breviores. 

These  muscles  are  parallel  in  their  obliquity,  with  the  ex- 
ternal intercostals,  and  are  not  very  obviously  separated  from 
them.  They  perform  the  same  service,  that  of  elevating  the 
ribs. 


FASCIA.  411 

CHAPTER  III. 

OF  THE  FASCIA  AND  MUSCLES  OF  THE  UPPER  EXTREMITIES. 
SECT.  I. FASCIA. 

THE  muscles  of  each  upper  extremity  are  invested  by  an  apo 
neurotic  membrane  called  the  Fascia  Brachialis,  which  extends 
from  the  shoulder  to  the  hand.  It  begins  at  the  base  and  spine 
of  the  scapula,  the  margin  of  the  acromion  process,  the  acromial 
extremity  of  the  clavicle,  and  from  the  cellular  membrane  in 
the  arm-pit,  and  extends  itself  over  all  the  muscles  of  the  dor- 
sum  of  the  scapula,  and  over  the  deltoid  muscle.  The  tendons 
of  the  latissimus  dorsi  and  pectoralis  major,  each  send  off  from 
their  margins  an  expansion  which  is  lost  in  it.  Below  the  spine 
of  the  scapula  it  is  strong  and  well  marked,  but  on  the  deltoid 
muscle,  as  well  as  on  the  muscles  of  the  arm,  its  desmoid  cha- 
racter is  by  no  means  so  well  developed,  though  it  still  retains  the 
appearance  of  a  distinct  membrane,  and  can  be  raised  up  as  such 
from  the  muscles.  On  the  fore  arm  its  ligamentous  appearance 
is  well  preserved,  and  extends  from  the  elbow  to  the  wrist  in- 
clusively. Its  longitudinal  fibres  there  are  well  secured  by 
transverse  ones. 

Above  the  condyles  of  the  os  humeri,  the  Fascia  Brachialis 
sends  down  to  the  bone  a  strong  tendinous  partition  to  each 
ridge,  and  which  runs  the  length  of  the  latter  from  its  upper 
end  to  the  condyle.  These  processes  separate  the  muscles  on 
the  back  of  the  arm  from  such  as  are  on  the  front  of  it,  and  are 
sometimes  called  the  Ligamentum  inter-musculare  internum  and 
externum.  They  afford  origin  to  many  muscular  fibres.  At  the 
bend  of  the  elbow,  the  fascia  brachialis  is  joined  by  a  fasciculus 
of  tendinous  matter  from  the  ulriar  margin  of  the  tendon  of  the 
biceps  flexor  cubiti,  and  which,  in  the  contraction  of  the  mus- 
cle, will  keep  the  fascia  tense. 

At  the  lower  extremity  of  the  fore  arm,  the  transverse  fibres, 
after  diminishing  sensibly,  become  more  numerous,  and  by  their 


412  FASCIA. 

attachments  to  the  several  ridges  on- the  back  of  the  radius  and 
of  the  ulna,  form  the  Ligamentum  Carpi  Dorsale.  This  liga- 
ment is  extended  from  the  styloid  or  outer  margin  of  the  radius, 
transversely  to  the  styloid  or  inner  margin  of  the  ulna,  to  the 
pisiform  bone,  and  to  the  fifth  metacarpal.  It  consists,  in  some 
measure,  of  two  portions:  of  which  the  superior  is  the  smaller 
and  thinner,  has  its  fibres  descending  from  the  radius  to  the  ulna, 
and  is  crossed,  in  part,  by  the  fibres  of  the  inferior  or  greater 
portion.  As  this  ligament  adheres,  with  great  strength,  to  the 
ridges  on  the  back  of  the  bones  of  the  fore  arm,  six  trochleae  for 
the  tendons  of  the  extensor  muscles  are  thus  formed.  The  first, 
or  that  next  to  the  styloid  process  of  the  radius,  contains  the 
tendons  of  the  first  two  extensors  of  the  thumb.  The  second  is 
'larger,  and  transmits  the  tendons  of  the  two  radial  extensors  of 
the  carpus.  The  third  is  small  and  oblique,  for  the  tendon  of 
the  third  extensor  of  the  thumb.  The  fourth  is  the  largest,  and 
is  for  the  tendons  of  the  extensor  communis  of  the  fingers.  The 
fifth  is  between  the  radius  and  the  head  of  the  ulna,  and  is  for 
that  tendon  of  the  extensor  communis  which  goes  to  the  little 
finger.  The  sixth  is  on  the  back  of  the  ulna,  and  is  for  the  ten- 
don of  the  extensor  carpi  ulnaris. 

The  inferior  margin  of  this  dorsal  ligament  of  the  wrist  does 
not  terminate  abruptly,  but  resuming  its  fascia-like  character, 
is  continued  over  the  back  of  the  wrist,  and  over  that  of  the 
hand  to  the  fingers.  In  this  progress  it  furnishes  an  envelope 
to  the  extensor  tendons,  and  is  very  much  blended  with  the  ob- 
lique fasciculi,  by  which  they  communicate  with  each  other. 

The  Fascia  Brachialis  affords  origin,  in  part,  to  the  muscles 
on  the  dorsum  of  the  scapula  below  its  spine;  on  the  arm  it  is 
not  so  intimately  connected  with  the  muscles,  but  on  the  fore 
arm  they  again  begin  to  arise,  in  part,  from  it.  In  its  whole 
course  partitions,  constituting  the  sheaths  of  the  rriuscles,  and 
which  consist,  for  the  most  part,  of  common  cellular  and  adipose 
membrane,  go  from  it  down  to  the  periosteum  and  interosseous 
ligament.  It  adheres  very  tightly  to  the  ulna,  from  the  ole- 
cranon  to  the  styloid  process.  On  its  cutaneous  surface  are 
found  all  the  superficial  veins,  nerves,  and  lymphatics  of  the 
arm.  Bichat  considers  this  membrane  as  the  best  example  of 


UPPER  EXTREMITIES.  413 

the  continuity  of  ligamentous  with  cellular  tissue,  and  conse- 
quently of  the  affinity  of  the  two. 

The  flexor  tendons  of  the  hand  and  fingers  are  held  down, 
by  the  Ligamentum  Carpi  Volare  or  the  Anterior  Annular  Li- 
gament of  the  Wrist.  It  is  a  very  strong  fasciculus  of  liga- 
mentous fibres,  which  subtends  the  concavity  of  the  carpal  bones 
in  front,  and  converts  it  into  the  large  oval  foramen  which  con- 
tains the  tendons.  It  is  attached  by  one  end  at  the  ulnar  side 
of  the  wrist,  to  the  hook-like  process  of  the  unciforme,  to  the 
cuneiforme,  and  to  the  pisiforme.  Its  fibres  go  straightly  across 
the  wrist  to  be  attached  by  their  other  extremities  to  the  radial 
end  of  the  trapezium,  and  of  the  scaphoides ;  and  may  be  readi- 
ly distinguished  from  the  fascia  brachialis  by  their  uniformly 
transverse  course;  by  their  superior  whiteness;  by  their  in- 
creased thickness ;  and  by  their  great  strength  and  unyielding 
nature.  Yet  the  superior  margin  of  this  ligament  is  partially 
continuous  with  the  fascia  brachialis,  and  the  inferior  margin 
with  the  aponeurosis  palmaris.  Several  of  the  little  muscles  of 
the  hand  arise  from  its  front  surface,  while  the  posterior  is  in 
contact  with  the  flexor  tendons. 

The  Aponeurosis  Palmaris  is  placed  just  below  the  skin,  and 
covers  the  middle  of  the  palm  of  the  hand.  It  is  triangular, 
and  has  its  apex  above,  where  it  arises  from  the  inferior  margin 
of  the  volar  or  anterior  annular  ligament  of  the  wrist,  and  from 
the  tendon  of  the  palmaris  longus;  it  spreads  out  in  its  descent, 
and  reaches  the  lower  ends  of  the  metacarpal  bones,  where  it 
is  divided  into  four  portions.  Each  of  these  portions  bifurcates 
and  passes  to  the  head  of  its  appropriate  metacarpal  bone,  to 
be  fixed  to  it  just  in  advance  of  the  inferior  palmar  ligaments. 
The  vacuity  of  the  bifurcation  permits  the  flexor  tendons  to  pass 
on  to  the  finger,  and  its  branches  are  held  together  by  transverse 
arid  reticulated  fibres,  the  interstices  of  which  are  filled  with 
fat.  The  lateral  margins  of  this  aponeurosis  send  off  a  thin 
membrane,  for  the  purpose  of  covering  the  muscles  of  the  thumb 
and  of  the  little  finger;  or,  in  other  words,  the  thenar  and  the 
hypothenar  eminences  in  the  palm  of  the  hand. 


35* 


414        •  MUSCLES. 

SECT.  II. — OF  THE  MUSCLES  OF  THE  SHOULDER. 

The  Ddtoides, 

Is  a  muscle  which  is  extended  over  the  top  of  the  shoulder 
joint,  and  forms  there  the  subcutaneous  cushion  of  flesh  which 
protects  and  gives  rotundity  to  the  articulation.  It  arises  from 
the  inferior  edge  of  the  whole  spine  of  the  scapula,  from  the 
circumference  of  the  acromion  process,  and  from  the  exterior 
third  of  the  clavicle.  Its  origin,  for  the  most  part,  is  tendinous 
and  fleshy  mixed;  but  at  its  posterior  part  it  is  entirely  tendi- 
nous. 

It  is  inserted,  by  a  tendinous  point,  into  the  triangular  rough 
surface  on  the  outer  side  of  the  os  humeri  near  its  middle.  Its 
general  configuration  is  triangular,  and  when  spread  out,  its 
upper  margin  is  much  more  extensive  than  one  would  suppose, 
as  it  is  opposed  to  the  entire  insertion,  of  the  trapezius.  Its 
fibres  do  not  converge  regularly  to  its  insertion  like  the  radii 
of  a  circle,  but  the  whole  muscle  is  divided  into  several  parts; 
the  interposition  of  inter-muscular  tendons  into  which,  affecting 
the  course  of  the  fibres,  makes  several  portions  of  the  deltoid 
look  penniform,  and  others  like  smaller  deltoids  introduced  into 
the  larger. 

The  deltoid  covers  the  insertion  of  the  pectoralis  major,  latis- 
simus  dorsi,  and  teres  major,  besides  that  of  the  other  muscles 
of  the  shoulder.  It  also  conceals  the  origin  of  the  biceps  flexor 
cubiti  and  of  the  coraco-brachialis.  Its  insertion  is  between  the 
triceps  extensor  and  the  biceps  flexor,  and  above  the  origin  of 
the  brachialis  interims.* 

It  raises  the  os  humeri. 

Between  the  superior  edge  of  the  deltoid,  the  acromion  pro- 
cess, and  the  subjacent  tendons  on  the  top  of  the  articulation, 
there  is  a  large  Bursa  Mucosa,  which  is  sometimes  partitioned 
off  into  two. 

*  Varieties.  Sometimes  a  fasciculus  arises,  between  the  infra-spinatus,  find 
the  teres  major,  or  from  the  inferior  costa  of  the  scapula,  and  joins  itself  to  the 
deltoids. 


MUSCLES  OF  THE  SHOULDER.  415 

The  Supra-Spinatus  Scapulce, 

Arises,  fleshy,  from  the  whole  fossa  supra-spinata,  which  it 
fills  up,  and  from  its  margins.  Forwards  it  terminates  in  a 
thick  robust  tendon  closely  connected  with  the  capsular  liga- 
ment of  the  joint,  and  which  passes  under  the  jugum  formed  by 
the  articulation  of  the  acromion  with  the  clavicle. 

It  is  inserted,  tendinous,  into  the  inner  face  of  the  great  tu- 
berosity  of  the  os  humeri. 

It  raises  the  arm,  and  turns  it  outwards. 

The  Infra-Spinal  us  Scapulce, 

Arises,  fleshy,  from  all  that  portion  of  the  dorsum  scapulae 
below  its  spine,  from  the  spine  as  far  as  the  cervix,  and  from 
the  several  margins  of  the  fossa  infra-spinata.  Its  fibres  pass 
obliquely  to  a  middle  tendon,  which  adheres  closely  to  the 
capsular  ligament,  and  goes  under  the  projection  of  the  acro- 
mion. 

This  tendon  is  inserted  into  the  middle  facet  of  the  greater 
tuberosity  of  the  os  humeri. 

The  infra-spinatus  rolls  the  os  humeri  outwards  and  back- 
wards. There  is  a  bursa  between  its  tendon  and  the  scapula.  • 

The  Tares  Minor, 

Is  situated  at  the  inferior  margin  of  the  infra-spinatus,  in  the 
fossa  of  the  inferior  costa  scapulae,  and  looks  very  much  like  a 
part  of  the  infra-spinatus,  to  which  it  occasionally  adheres  so 
closely  as  to  be  separated  with  difficulty.  It  arises,  fleshy,  from 
the  whole  of  the  fossa,  and  the  margins  of  the  inferior  costa,  in 
the  space  from  the  cervix  of  the  bone  to  within  an  inch  or  so 
of  its  angle. 

It  is  inserted,  tendinous  and  fleshy,  into  the  outer  facet  of 
the  great  tuberosity  of  the  os  humeri,  just  below  the  infra-spi- 
natus. 

It  draws  the  os  humeri  downwards  and  backwards,  and  ro- 
tates it  outwards. 


416  MUSCLES. 


The  Teres  Major, 

Is  situated  at  the  inferior  edge  of  the  teres  minor.  It  arises, 
fleshy,  from  the  posterior  surface  of  the  angle  of  the  scapula, 
and  from  a  small  part  of  its  inferior  costa ;  the  interstice  be- 
tween it  and  the  teres  minor  is  considerable. 

It  is  inserted,  by  a  broad  tendon,  into  the  internal  ridge  of 
the  groove  of  the  os  humeri,  along  with  the  tendon  of  the  la- 
tissimus  dorsi.  Their  tendons,  at  first,  are  closely  united,  but 
afterwards  there  is  an  intermediate  cavity  lubricated  with  sy- 
novia. The  tendon  of  the  latissimus  dorsi  is  anterior,  and  the 
lower  edge  of  the  teres  extends  farther  down  the  arm  than  it. 

It  rolls  the  humerus  inwards,  and  draws  it  downwards  and 
backwards. 

The  Subscapularis, 

Occupies  all  the  thoracic  surface  of  the  scapula,  being  be- 
tween it  and  the  serratus  major.  It  arises,  fleshy,  from  the 
whole  base,  superior  and  inferior  costa,  and  costal  surface  of 
the  scapula;  it  is  divided  into  several  columns,  which  look  some- 
what like  distinct  muscles,  but  they  all  terminate  in  a  thick  ro- 
bust tendon  that  adheres  to  the  inferior  surface  of  the  capsular 
ligament. 

This  tendon  is  inserted  into  the  lesser  tuberosity  of  the  os  hu- 
meri. 

The  subscapularis  rolls  the  bone  inwards  and  draws  it  down- 
wards. Between  it  and  the  neck  of  the  scapula,  there  is  a 
bursa,  which,  as  mentioned,  communicates  with  the  articula- 
tion. 


SECT.   III. OF  THE   MUSCLES  OF  THE  ARM. 

Tfie  Biceps  Flexor  Cubiti. 

This   muscle  is  just   beneath  the  fascia   and  integuments, 
and  forms  the  swell  so  obvious  in  the  middle  front  part  of  the 


MUSCLES  OF  THE  ARM.  417 

arm.  It  arises  by  two  heads.  The  first,  called  the  long,  is  a 
round  tendon  which  comes  from  the  superior  extremity  of  the 
glenoid  cavity  of  the  scapula,  passes  through  the  shoulder  joint 
and  through  the  groove  of  the  os  humeri ;  the  second  head  arises 
tendinous  from  the  extremity  of  the  coracoid  process  of  the  sca- 
pula, in  company  with  the  coraco-brachialis  muscle.  The  fleshy 
bellies  in  which  these  tendons  terminate,  unite  with  each  other, 
several  inches  below  the  shoulder  joint,  to  form  a  common  mus- 
cle. At  first  they  are  only  connected  by  loose  cellular  sub- 
stance ;  but,  about  half-way  down  the  arm,  they  are  insepara- 
bly united. 

The  biceps  terminates  below  in  a  flattened  oval  tendon,  which 
passes  in  front  of  the  elbow  joint,  to  be  inserted  into  the  poste- 
rior rough  part  of  the  tubercle  of  the  radius.  A  bursa  mucosa 
is  placed  between  the  tendon  and  the  front  of  the  tubercle,  the 
surface  of  the  latter  being  covered  with  cartilage.  From  the 
ulnar  side  of  this  tendon  proceeds  the  aponeurosis  running  into 
that  of  the  fore  arm. 

The  relative  position  of  the  biceps  is  as  follows:  Its  long 
head  is  first  within  the  cavity  of  the  capsular  ligament,  and  then 
between  the  tendons  of  the  latissimus  dorsi  and  pectoralis  ma- 
jor, where  it  is  bound  down  by  strong  ligamentous  fibres.  The 
tendon  below  is  superficial,  and  may  be  easily  felt  by  flexing 
the  fore-arm,  but  its  insertion  dips  down  between  the  pronator 
teres  and  supinator  radii  longus. 

This  muscle  flexes  the  fore-arm.* 


The  Coraco-Brachialis, 

Is  situated  on  the  upper  internal  side  of  the  arm,  at  the  inner 
edge  of  the  short  head  of  the  biceps  muscle,  with  which  it  is 
connected  for  three  or  four  inches.  It  arises  tendinous  and 
fleshy  from  the  middle  facet  of  the  point  of  the  coracoid  pro- 


*  Varieties.  Sometimes  the  division  of  the  muscle  is  continued  to  the  elbow; 
sometimes  there  is  a  third  head,  coming  either  from  the  internal  face  of  the  os 
humeri,  or  from  the  brachialis  internus;  very  rarely,  the  number  of  heads^has 
been  multiplied  to  five,  thereby  making  a  close  approximation  to  the  arrangement 
in  birds.  This  muscle  is  very  liable  to  anomalies. 


418  MUSCLES. 

cess  of  the  scapula,  in  common  with  the  short  head  of  the  bi. 
ceps  muscle. 

It  is  inserted,  tendinous  and  fleshy,  into  the  internal  side  of 
the  middle  of  the  os  humeri,  by  a  rough  ridge,  just  below  the 
tendons  of  the  latissimus  dorsi  and  teres  major,  and  in  front  of 
the  brachialis  externus  or  third  head  of  the  triceps.  The  lower 
end  of  this  muscle  is  attached  to  the  inter-muscular  ligament  of 
the  internal  side  of  the  os  humeri,  which  separates  the  brachi- 
alis interims  from  the  third  head  of  the  triceps. 

This  muscle  draws  the  arm  upwards  and  forwards.* 

The  Brachialis  Interims, 

Is  situated  immediately  beneath  the  biceps,  and  is  concealed 
by  it,  excepting  its  outer  edge.  It  has  a  bifurcated  fleshy  ori- 
gin from  the  middle  front  face  of  the  os  humeri  on  each  side 
of  the  insertion  of  the  deltoid,  and  its  origin  is  continued  fleshy 
from  this  point  downwards,  from  the  whole  front  of  the  bone 
to  within  a  very  small  distance  of  its  articular  surface. 

It  is  inserted,  by  a  strong  short  tendon,  into  the  rough  surface 
at  the  root  of  the  coronoid  process  of  the  ulna.  A  bursa  some- 
times exists  between  the  tendon  of  the  brachialis  internus,  that 
of  the  biceps,  the  supinator  brevis,  and  the  elbow  joint. 

The  brachialis  flexes  the  fore  arm,  and,  by  passing  in  front  of 
the  elbow  joint,  strengthens  the  latter  very  much.  Its  lower 
part  lies  under  the  tendon  of  the  biceps,  and  between  the  pro- 
nator  teres  and  the  supinator  longus.f 

*  Varieties.  This  muscle  being  generally  penetrated  by  the  musculo-cuta- 
neous  nerve,  the  perforation  thus  made  sometimes  exists  as  a  fissure,  extending 
the  length  of  the  lower  half  of  the  muscle;  on  other  occasions  the  fissure  is  so 
long  as  to  divide  the  muscle  completely  into  two. 

f  Varieties.  Sometimes,  at  its  external  margin,  there  exists  a  smaller  brachia- 
lis internus  muscle,  which  arises  from  about  the  same  point  of  the  humerus,  and 
is  inserted  into  the  same  part  of  the  cubitus.  Sometimes  it  detaches  a  fasciculus 
which  joins  the  biceps  muscle.  Sometimes  its  posterior  part  is  distinct  from  the 
anterior.  Sometimes  a  fasciculus  of  it  runs  along  the  supinator  longus  of  the  fore 


MUSCLES  OF  THE  ARM.  419 

The  Triceps  Extensor  Cubiti,  or  Brachii, 

Forms  the  whole  of  the  fleshy  mass  on  the  back  of  the  arm ; 
it  therefore  occupies  the  space  between  the  integuments  and  the 
bone.  It  arises  by  three  heads.  The  first,  called  Lorigus, 
comes,  by  a  flattened  tendon,  between  the  teres  major  and  the 
minor  muscle,  from  a  rough  ridge  on  the  inferior  edge  of  the 
cervix  scapulas.  The  second,  called  the  Brevis,  arises  by  a  sharp, 
tendinous,  and  fleshy  beginning,  from  a  slight  ridge  on  the  outer 
back  part  of  the  os  humeri,  just  below  its  head.  The  third  head, 
called  Brachialis  Externus,  arises,  by  an  acute  fleshy  beginning, 
from  the  inner  side  of  the  os  humeri  near  the  insertion  of  the 
teres  major.  This  muscle,  both  at  its  external  and  internal 
edge,  is  separated  from  the  muscles  in  front  of  the  arm  by  the 
external  and  internal  inter-muscular  ligaments,  which  arise  near 
the  middle  of  the  os  humeri,  and  run  to  the  condyles  respec- 
tively. The  whole  back  of  the  os  humeri,  as  well  as  the  pos- 
terior surface  of  these  inter-muscular  septa,  is  occupied  by  the 
origin  of  the  triceps.  The  muscular  fibres  run  in  various  direc- 
tions, according  to  their  respective  heads  and  places  of  origin. 

At  the  inferior  end  of  the  muscle  is  found  a  broad  tendon, 
which  covers  its  posterior  face.  This  tendon  is  inserted  into 
the  base  or  back  part  of  the  olecranon,  and  the  ridge  leading 
down  the  ulna  on  its  radial  side.  The  bellies  of  the  triceps 
unite  above  the  middle  of  the  os  humeri,  but  the  interstices  be- 
tween them  may  be  observed  much  lower  down.  There  is  a 
bursa  between  the  tendon  and  the  olecranon  process ;  besides 
which,  there  is  sometimes  another  on  each  side  of  the  first. 

The  triceps  extends  the  fore  arm. 

The  Jlnconeus, 

Is  a  small  triangular  muscle,  just  beneath  the  skin,  at  the  outer 
posterior  part  of  the  elbow  joint.  It  arises  tendinous  from  the 
posterior  lower  part  of  the  external  condyle  of  the  os  humeri, 
adheres  to  the  capsular  ligament  of  the  joint,  and  is  partly  co- 
vered by  the  tendon  of  the  triceps. 

It  is  inserted,  fleshy  and  thin,  into  the  ridge  leading  from  the 


420  MUSCLES. 

olecranon,  on  the  outer  part  of  the  upper  end  of  the  ulna,  and 
into  the  triangular  depression  found  there;  so  as  to  fill  it  up. 
It  extends  the  fore  arm. 


SECT.  IV. OF  THE  MUSCLES  OF  THE  FORE  ARM. 

There  are  eight  muscles  on  the  front  of  the  fore  arm,  some 
of  which  are  superficial,  and  others  deep-seated.  They,  for  the 
most  part,  are  either  directly  or  indirectly  flexors  of  the  fore 
arm  and  hand,  and  in  their  origin  adhere  very  much  by  the  ten- 
dinous partitions,  called  Inter-muscular  Ligaments. 

1.   The  Pronator  Radii  Teres, 

Is  just  beneath  the  fascia  of  the  fore  arm,  and  forms  the  ra- 
dial side  of  the  muscles  of  the  internal  condyle.  It  arises, 
fleshy,  from  the  anterior  face  of  the  internal  condyle  of  the  os 
humeri,  and  tendinous  from  the  coronoid  process  of  the  ulna. 
It  passes  very  obliquely  across  the  fore  arm,  at  the  internal  edge 
of  the  brachialis  internus  muscle,  and  is  inserted,  tendinous  and 
fleshy,  into  the  external  back  part  of  the  radius,  just  below  the 
insertion  of  the  supinator  radii  brevis,  occupying  about  two 
inches  of  the  middle  of  the  bone. 

It  rolls  the  hand  inwards.* 

2.  The  Flexor  Manus  vel  Carpi  Radialis, 

Is  placed  at  the  ulnar  side  of  the  last  muscle,  and  is  also  su- 
perficial. It  arises,  by  a  narrow  tendon,  from  the  lower  front 
part  of  the  internal  condyle  of  the  humerus,  fleshy  from  the  in- 
ter-muscular ligaments,  fascia,  and  from  the  upper  part  of  the 
ulna.  It  forms  a  thick  fleshy  belly,  terminating  below  in  a  ten- 
don, which  passes  under  the  anterior  annular  ligament  of  the 
wrist,  and  runs  through  a  groove  in  the  os  trapezium. 

It  is  inserted,  tendinous,  into  the  base  of  the  metacarpal  bone 
of  the  fore  finger,  in  front. 

*  Varieties.     Sometimes  it  is  double. 


MUSCLES  OF  THE  FORE  ARM.  421 

There  is  a  bursa  between  the  lower  extremity  of  its  tendon 
and  the  trapezium ;  the  tendon  is  there  held  down  by  ligamen- 
tous  fibres. 

It  bends  the  hand,  and  draws  it  towards  the  radius. 


3.   The  Palmaris  Longus, 

Is  at  the  ulnar  side  of  the  flexor  carpi  radialis,  and  is  super- 
ficial. It  is  a  small  short  muscle,  terminating  in  a  long  slen- 
der tendon,  and  arises  by  a  small  tendon  from  the  internal  con- 
dyle,  and  fleshy  from  the  inter-muscular  ligament  on  each  of  its 
sides. 

It  is  inserted,  tendinous,  into  the  upper  margin  of  the  liga- 
mentum  carpi  annulare  anterius,  near  the  root  of  the  thumb; 
and  a  division  of  its  tendon  passes  on  to  the  aponeurosis  pal- 
maris. 

It  bends  the  hand,  and  makes  tense  the  palmar  aponeurosis.* 

4.  The  Flexor  Manus  vel  Carpi  Ulnar  is, 

Occupies,  among  the  superficial  muscles,  the  ulnar  side  of  the 
fore  arm.  It  arises,  tendinous,  from  the  internal  condyle  of  the 
os  humeri,  fleshy  from  the  upper  internal  side  of  the  olecranon, 
and  by  a  tendinous  expansion,  being  a  part  of  the  fascia  of  the 
fore  arm,  from  the  ridge  at  the  internal  side  of  the  ulna  to  with- 
in three  or  four  inches  of  the  wrist. 

It  is  inserted  into  the  upper  side  of  the  os  pisiforme  by  a 
round  tendon,  which  arises  early  at  the  radial  margin  of  the 
muscle,  and  receives  the  muscular  fibres.  Sometimes  the  ten- 
don is  continued  over  the  os  pisiforme,  so  as  to  be  likewise  in- 
serted into  the  base  of  the  metacarpal  bone  of  the  little  finger. 
There  is  a  loose  bursa  at  the  junction  of  the  tendon  with  the 
pisiforme. 

It  bends  the  hand,  and  draws  it  towards  the  ulna. 

*  Varieties.  Sometimes  it  is  deficient  in  both  arms;  sometimes  the  middle  part 
only  is  fleshy;  sometimes  the  belly  goes  almost  to  the  wrist. 

VOL.  I.— 36 


422  MUSCLES.  f.-  . 

5.  The  Flexor  Digitorum  Sublimis  Perforates, 

Is  concealed  very  much  by  the  muscles  just  enumerated,  in 
consequence  of  being  placed  between  them.  To  get  a  good 
view  of  its  origin,  they  all  should  be  cut  away  from  the  os  hu •• 
meri.  It  arises,  tendinous  and  fleshy,  from  the  internal  con- 
dyle  of  the  os  humeri,  tendinous  from  the  coronoid  process  of 
the  ulna,  and  fleshy  from  the  tubercle  of  the  radius;  the  latter 
part  of  its  origin  being  extended,  tendinous  obliquely,  for  three 
or  four  inches  from  that  line  of  the  radius  which  is  at  the  upper 
margin  of  the  supinator  radii  brevis.  With  these  origins  the 
muscle  spreads  over  the  front  of  the  fore  arm  at  its  upper  part, 
from  the  radial  to  the  ulnar  margin. 

Four  distinct  tendons  pass  from  the  lower  end  of  the  muscle? 
which  commence  much  above  the  wrist,  pass  beneath  its  ante- 
rior ligament,  and,  having  reached  the  palm  of  the  hand,  diverge 
to  the  several  fingers.  A  tendon  is  appropriated  to  each  finger, 
and  passes  in  front  of  the  metacarpal  bone  to  the  phalanges,  be- 
ing inserted,  after  having  split  into  two,  into  the  angles  formed 
by  the  junction  of  the  cylindrical  and  flat  surface  of  the  second 
phalanx  near  its  middle. 

It  bends  the  second  phalanges  on  the  first;  its  action  may  also 
be  continued  so  as  to  clench  the  hand  and  to  bend  it  on  the  fore 
arm.* 


6.   The  Flexor  Digitorum  Profttndus  Perforates, 

Is  beneath  the  flexor  sublimis  and  the  flexor  ulnaris.  It  arises, 
fleshy,  from  the  oblong  concavity  of  the  ulna,  along  the  inner 
side  of  the  coronoid  and  the  olecranon  process,  fleshy  from 
the  lower  margin  of  the  base  of  the  coronoid  process,  from  the 
ulnar  portion  of  the  interosseous  ligament,  and  from  the  front  of 
the  upper  two-thirds  of  the  ulna. 


*  Varieties.  The  tendon  to  the  little  finger  is  sometimes  wanting,  in  which 
case  the  deficiency  is  supplied  by  the  tendon  of  the  flexor  profunchis.  Some- 
timjs  the  section  of  this  muscle  which  belongs  to  the  fore  finger,  is  insulated 
from  the  rest  of  it,  by  a  long  fissure,  and,  moreover,  divided  by  a  middle  tendon, 
into  two  fleshy  portions. 


MUSCLES  OF  THE  FORE  ARM.  423 

The  tendons  of  this  muscle  are  different  from  those  of  the 
other;  they  commence  in  front  of  it,  like  a  tendinous  membrane, 
which  is  gradually  divided  into  several  fasciculi,  adhering  to 
each  other  by  cellular  membrane.  The  fasciculated  character 
of  the  tendons  is  still  preserved  when  they  go  under  the  ante- 
rior carpal  ligament,  and  until  they  begin  to  disperse  as  distinct 
tendons  to  each  of  the  fingers. 

Each  tendon,  going  in  front  of  its  metacarpal  bone  and  of  the 
corresponding  phalanges,  gets  through  the  slit  in  the  flexor  sub- 
limis,  and  is  inserted  into  the  front  part  of  the  root  of  the  third 
phalanx  of  its  respective  finger. 

It  bends  the  last  phalanges  of  the  fingers,  and  may,  by  in- 
creased action,  flex  the  hand  like  the  preceding  muscle.* 

7,   The  Flexor  Longus  Pollicls, 

Lies  in  front  of  the  radius,  but  beneath  the  flexor  sublimis. 
It  arises  by  an  acute  fleshy  beginning,  from  the  radius  just  be- 
low its  tubercle;  also  fleshy  from  the  middle  two-thirds  of  the 
front  of  this  bone,  and  from  the  radial  portion  of  the  interosse- 
ous  ligament.  The  body  of  the  muscle  is  joined  by  a  small 
fleshy  slip  having  a  tendinous  origin  from  the  internal  condyle 
of  the  os  humeri. 

A  tendon  is  formed  early  on  the  ulnar  margin  of  this  mus- 
cle, and  to  which  the  fibres  pass  obliquely.  The  tendon  goes 
under  the  annular  ligament  of  the  wrist,  through  the  fossa  formed 
in  the  short  flexor  muscle  of  the  thumb,  and  between  the  sesa- 
moid  bones,  to  be  inserted  into  the  base  of  the  second  phalanx 
of  the  thumb. 

From  the  inferior  end  of  the  fore  arm  to  the  middle  of  the 
first  phalanx,  the  tendon  is  invested  by  its  appropriate  bursa. 

It  bends  the  last  joint  of  the  thumb. 

The  several  Flexor  tendons,  as  they  pass  under  the  anterior 
annular  ligament  of  the  wrist,  are  surrounded  by  the  superior 
Bursa  Mucosa.  It  begins  about  an  inch  and  a  half  above  the 

*  Varieties.  Sometimes  a  distinct  fasciculus  comes  from  the  internal  condyle 
to  join  it;  sometimes  a  fasciculus  comes  from  the  flexor  longus  pollicis,  and  ter- 
minating in  a  tendinous  expansion,  is  inserted  into  the  tendon  which  the  flexor 
profundus  sends  to  the  fore  finger. 


424  MUSCLES. 

radio-carpal  articulation,  and  extends  to  the  lower  margin  of  the 
annular  ligament.  It  adheres  by  its  circumference  to  this  liga- 
ment and  to  the  capsule  of  the  joint;  internally,  it  sends  in  a 
considerable  number  of  processes,  whereby  each  tendon  is  sur- 
rounded, and  connected  to  the  adjoining  tendons;  while  at  the 
same  time  no  restraint  is  put  upon  the  natural  motions  of  the 
part.  In  its  texture  this  bursa  resembles  a  dense  and  elastic 
cellular  membrane. 

In  addition  to  this,  the  flexor  tendons,  as  they  pass  from  the 
root  to  the  extremity  of  each  finger,  are  surrounded  by  a  syno- 
vial  bursa;  which  by  its  secretion  continually  lubricates  them, 
and  permits  them  to  play  freely  backwards  and  forwards,  ac- 
cording to  the  flexions  and  extensions  of  the  fingers.  These 
mucous  or  synovial  sheaths,  begin  a  little  distance  above  the 
first  joint  of  the  finger,  adhere  there  to  both  flexor  tendons,  and 
extend  to  about  the  middle  of  the  last  phalanx.  They  give  to 
the  tendons  a  very  polished  lubricated  surface;  are  reflected 
over  the  anterior  flat  faces  of  the  phalanges,  being  separated 
from  them  by  a  small  quantity  of  adipose  matter;  they  are  also 
reflected  over  the  anterior  faces  of  the  capsular  ligaments,  and 
line  of  the  vaginal  ligaments. 

The  Vaginal  Ligaments  of  the  fingers  (Ligamenta  Vaginalia) 
bind  down  the  flexor  tendons  and  keep  them  applied  to  the 
fronts  of  the  phalanges.  They  are  'of  the  same  extent  from 
above  downwards,  with  the  mucous  sheaths  just  mentioned,  and 
are  stretched  between  the  ulnar  and  the  radial  margins  of  the 
phalanges.  The  fibres  of  which  they  consist  pass  for  the  most 
part  transversely,  and  are  of  a  fibre-cartilaginous  character. 
These  fibres  diminish  in  number  towards  the  end  of  each  finger, 
and  are  stronger  on  the  fore  finger  than  on  any  of  the  others. 
In  front  of  the  metacarpo-phalangial  articulations,  and  the  phu- 
langial  articulations,  the  vaginal  ligaments  are  much  thinner 
than  elsewhere,  in  order  to  permit  the  free  flexions  of  the  fingers. 
The  structure,  indeed,  at  these  points,  is  strongly  marked  off 
by  its  diminished  thickness ;  and  though  the  course  of  the  fibres 
is  the  same  from  side  to  side,  yet  some  anatomists  have  thought 
it  worth  while  to  designate  it,  particularly  under  the  name  of 
Annuli  Juncturarum  Ligamentosi. 

Within  the  vaginal   ligaments  small  tendinous  fraena  arise 
from  the  first  and  second  phalanges;  they  vary  in  number  in 


MUSCLES  OF  THE  FORE  ARM.  425 

different  individuals,  and  run  obliquely  forwards,  some  to  ter- 
minate in  the  flexor  profundus  tendons,  and  others  in  those  of 
the  flexor  sublimis ;  they  are  called  Vincula  Accessoria,  and 
are  covered  by  a  reflection  of  the'synovial  sheath. 


8.   The  Pronator  Quadratics, 

Is  just  above  the  carpal  surfaces  of  the  radius  and  ulna,  and 
between  the  other  muscles  and  the  bone.  In  the  adult  it  is 
about  two  inches  wide,  and  its  fibres  run  across  the  fore  arm. 
It  arises,  fleshy  and  tendinous,  from  the  ridge  at  the  inner  sur- 
face of  the  ulna,  near  its  lower  extremity,  and  from  the  front 
of  the  bone. 

It  is  inserted  into  the  corresponding  front  surface  of  the  ra- 
dius. 

It  rotates  the  radius  inwards.* 


Of  the  Muscles  on  the  back  of  the  Fore  Arm. 

These  muscles  are  ten  in  number.  They  arise,  for  the  most 
part,  from  the  external  condyle,  and  the  ridge  leading  to  it,  and 
are  extensors  either  of  the  fore  arm,  or  of  the  fingers  and  thumb. 
Their  origins  are  less  blended  with  each  other  than  those  of  the 
flexor  muscles;  nevertheless,  between  several  of  them  there  are 
inter-muscular  ligaments  which  connect  them.  They  are  su- 
perficial and  deep-seated. 


1.  The  Supinator  Radii  Longus, 

Is  situated  along  the  radial  edge  of  the  fore  arm,  immediate- 
ly beneath  the  integuments.  It  arises,  fleshy  and  tendinous, 
from  the  higher  part  of  the  ridge  leading  to  the  external  can- 
dyle;  commencing  just  below  the  insertion  of  the  deltoid  mus- 
cle, and  being  here  placed  between  the  brachialis  internus  and 
the  outer  head  of  the  triceps.  It  forms  a  thick  fleshy  belly, 
constituting  the  external  margin  of  the  arm,  about  the  elbow 

*  Varieties.  This  muscle  in  some  very  rare  cases  does  not  exist.  Sometimes 
it  consists  in  two  layers  whose  fibres  cross  each  other.  In  a  case  noticed  in  the 
Pennsylvania  Hospital  by  Dr.  J.  R.  Barton,  it  consisted  in  two  triangular  pieecs, 
the  bases  of  which  were  reversed. 

36* 


426  MUSCLES. 

joint;  and  terminates  about  the  middle  of  the  radius  in  a  flat 
tendon. 

Itjis  inserted,  by  the  tendon,  into  a  small,  rough  ridge,  on 
the  outer  side  of  the  radius  just  above  its  styloid  process. 

It  rolls  the  radius  outwards. 


2.   The  Extensor  Carpi  Radialis  Longior, 

Is  situated  beneath  the  former  muscle.  It  arises,  tendinous 
and  fleshy,  from  the  space  of  the  external  ridge  of  the  os  hu- 
meri,  between  the  supinator  longus  and  the  external  condyle. 
It  forms  a  short,  fleshy  belly,  which  terminates  in  a  flat  tendon 
above  the  middle  of  the  radius. 

It  is  inserted,  by  this  tendon,  into  the  posterior  part  of  the 
root  of  the  metacarpal  bone  of  the  fore  finger,  near  the  thumb. 

The  tendon  of  this  muscle  is  surrounded  by  a  synovial  sheath, 
at  the  place  where  it  passes  the  lower  end  of  the  radius,  under 
the  posterior  carpal  ligament.  Another  bursa  exists,  also,  at 
its  insertion;  which,  on  one  occasion,  I  found  so  much  enlarged 
in  a  young  woman,  as  to  require  its  extirpation:  the  operation 
was  fully  successful. 

It  extends  the  hand.* 


3.   The  Extensor  Carpi  Radialis  Brevior, 

Is  beneath  the  last,  but  projects  somewhat  beyond  it.  It 
arises,  tendinous,  from  the  posterior  and  lower  part  of  the  ex- 
rernal  condyle,  and  from  the  external  lateral  ligament  of  the 
elbow  joint.  It  forms  a  thick,  fleshy  belly,  placed  along  the 
radius,  and  terminates  in  a  flat  tendon  about  the  middle  of  that 
bone. 

Its  tendon,  becoming  rounded,  is  inserted  into  the  posterior 
part  of  the  base  of  the  metacarpal  bone  of  the  second  finger, 
and  has  a  bursa  beneath  its  insertion,  and  another  at  the.  wrist. 

It  extends  the  hand.f 

*  Varieties.  Sometimes  a  small  fasciculus  is  detached  from  its  posterior  mar- 
gin, and  has  a  tendinous  insertion  into  the  third  metacarpal  bone. 

t  Varieties.  Sometimes  this  muscle  is  so  blended  with  the  preceding,  as  to  be 
*n  common  with  it. 


MUSCLES  OF  THE  FORE  ARM.  427 


4.   The  Extensor  Carpi  Ulnans, 

Is  superficial,  and  placed  principally  parallel  with  the  ulna. 
It  arises,  tendinous,  from  the  external  condyle,  fleshy  from  the 
inter-muscular  ligament,  and  inside  of  the  fascia.  Crossing 
very  obliquely  the  upper  part  of  the  radius  and  the  ulna,  it  also 
arises  fleshy  from  the  back  part  of  the  latter  bone.  Its  fibres 
terminate  obliquely  in  a  tendon  which  goes  through  the  groove 
of  the  ulna,  and  is  there  furnished  with  a  bursa. 

It  is  inserted,  by  its  tendon,  into  the  ulnar  side  of  the  base  of 
the  metacarpal  bone  of  the  little  finger. 

It  extends  the  hand.* 


5.   The  Extensor  Digitorum  Communis, 

Is  superficial,  being  placed  between  the  extensor  ulnaris  and 
the  extensor  radialis  brevior.  It  arises,  tendinous,  from  the  ex- 
ternal condyle,  and  fleshy  from  the  inter-muscular  ligament  of 
the  contiguous  muscles.  As  it  approaches  the  wrist  it  sends  off 
four  tendons,  which  pass  together  through  a  common  groove  on 
the  back  of  the  radius.  On  the  back  of  the  hand  these  tendons 
diverge,  and  near  the  roots  of  the  fingers  send  cross  slips  to 
each  other. 

Each  tendon  goes  to  its  respective  finger,  and  covers  the 
whole  posterior  part  of  it,  being  spread  out  into  a  membrane 
which  adheres  to  the  phalanges  from  the  root  of  the  first  to  the 
root  of  the  last.  The  precise  mode  of  the  insertion  of  these 
tendons  is  as  follows :  on  the  back  of  the  first  phalanx,  the  la- 
teral margins  of  these  tendons  are  joined  by  the  tendons  of  the 
lumbricales  and  interossei;  and  the  tendinous  membrane,  thus 
formed,  simply  adheres  by  condensed  cellular  membrane  to  the 
whole  back  of  the  first  phalanx ;  the  middle  part  of  this  tendon 
then  passes  on  to  be  inserted  near  the  articular  margin  of  the 
base  of  the  second  phalanx;  and  the  two  lateral  parts  of  the 
tendinous  membrane,  after  keeping  separate  for  some  distance, 

*  Varieties.  Sometimes  its  tendon  is  joined,  by  a  small  fasciculus,  to  the  ex- 
tensor  tendon  of  the  little  finger. 


428  MUSCLES. 

unite,  and  are  jointly  inserted  into  the  back  of  the  base  of  the 
third  phalanx. 

The  section  of  this  muscle  appropriated  to  the  little  finger 
has  a  distinct  appearance,  and  frequently  its  tendon  goes  through 
a  separate  fossa  in  the  radius,  from  which  causes  it  has  obtained 
the  name  of  Auricularis.  A  bursa  invests  these  tendons  at  the 
wrist  as  they  pass  through  their  groove,  and  is  single  above ; 
but,  in  following  the  course  of  the  tendons,  like  them  it  divides 
and  follows  each  tendon  respectively  to  the  base  of  the  first 
phalanx. 

This  muscle  extends  all  the  joints  of  the  fingers,  being  the 
antagonist  of  the  flexors.* 

6.  TJte  Supinalor  Radii  Brevis, 

Can  only  be  well  seen  by  detaching  the  origin  of  the  afore- 
said muscles;  it  will  then  be  found  in  contact  with  the  radius, 
making  a  close  investment  of  its  head  and  upper  third.  It  arises, 
tendinous,  from  the  external  condyle  of  the  os  humeri,  tendi- 
nous and  fleshy  from  the  ridge  on  the  posterior  radial  edge  of 
the  ulna  which  descends  from  its  coronoid  process. 

Its  fibres  surround,  obliquely,  the  upper  external  part  of  the 
radius,  and  are  inserted  into  its  tubercle,  and  into  its  oblique 
rough  ridge,  corresponding  with  the  upper  margin  of  the  pro- 
nator  teres.  At  the  interstice  between  the  radius  and  ulna, near 
the  anterior  edge  of  this  muscle,  a  fleshy  slip  is  occasionally 
seen  which  passes  from  the  radial  side  of  the  coronoid  process 
to  the  ulnar  edge  of  the  radius. 

This  muscle  rotates  the  radius  outwards.f 


7.   The  Extensor  Ossis  Metacarpi  Potticis  Manns, 

Arises,  fleshy,  from  the  posterior  part  of  the  ulna  immedi- 
ately below  the  anconeus,  from  the  interosseous  ligament,  and 

*  Varieties.  It  sometimes  sends  a  double  tendon  to  the  little  finger,  in  which 
case  the  auriculuris  is  more  distinct  than  usual,  and  the  tendon  next  to  the  ulna 
runs  through  a  distinct  trochlea  in  the  posterior  carpal  ligament. 

t  Varieties.  Sometimes  the  superior  part  is  separated  from  the  inferior;  some» 
times  the  muscle  is  double.. 


MUSCLES  OF  THE  FORE  ARM.  429 

from  the  back  part  of  the  radius  just  below  the  insertion  of  the 
supinator  brevis.  It  terminates  in  a  rounded  tendon  which 
passes  over  the  tendons  of  the  radial  extensors,  and  through  a 
groove  on  the  styloid  side  of  the  lower  end  of  the  radius.  The 
tendon  is  there  invested  by  a  bursa. 

It  is  inserted,  by  its  tendon,  into  the  base  of  the  metacarpal 
bone  of  the  thumb,  and  into  the  external  side  of  the  trapezium. 

It  extends  the  metacarpal  bone  of  the  thumb.* 

8.  The  Extensor  Minor  Pollicis  Mantis, 

Is  at  the  ulnar  side  of  the  last  muscle.  It  arises,  tendinous, 
from  the  back  of  the  ulna  below  its  middle,  and  fleshy  from  the 
interosseous  ligament.  It  adheres  to  the  radius,  and  terminates 
in  a  tendon  which  passes  through  the  groove  in  the  styloid  side 
of  the  radius,  along  with  the  last  named  muscle. 

It  is  inserted  into  the  first  phalanx  of  the  thumb,  by  its  ten- 
don, which  is  extended  to  the  root  of  the  second  phalanx. 

It  extends  the  first  phalanx/f 

9.  The  Extensor  Major  Pollicis  Manus, 

Arises,  by  a  small  tendinous,  and  an  extensive  fleshy  origin, 
from  the  back  of  the  ulna  above  its  middle,  and  from  the  inte- 
rosseous ligament,  also  from  the  back  of  the  radius;  it  terminates 
near  the  wrist,  in  a  tendon  which  passes  through  the  groove  on 
the  back  of  the  radius  near  the  ulna.  The  belly  of  this  muscle 
conceals,  very  much,  the  other  extensors  of  the  thumb. 

It  is  inserted,  by  its  tendon,  into  the  oblong  transverse  tu- 
bercle, on  the  back  of  the  base  of  the  second  phalanx  of  the 
thumb.  Its  tendon  is  furnished  with  one  synovial  sheath,  at  the 
inferior  extremity  of  the  radius,  which  extends  to  the  carpus,  and 
another  which  is  smaller,  and  is  placed  upon  the  carpus  and 
upon  the  base  of  the  first  metacarpal  bone. 

It  extends  the  second  phalanx.J 

*  Varieties.  This  muscle  is  sometimes  double,  and  has  several  other  modifi- 
cations which  it  is  unnecessary  to  state. 

f  Varieties.  This  muscle  is  sometimes  only  an  appendage  of  the  preceding. 
Occasionally,  its  tendon  is  confounded  with  that  of  the  succeeding  muscle. 

t  Varieties.    Sometimes  this  muscle  is  completely  double. 


430  MUSCLES. 

The  tendons  of  the  last  two  muscles  are  much  connected  with 
each  other,  and  are  spread  in  the  form  of  a  membrane  on  the 
back  of  the  thumb,  after  the  manner  of  the  extensor  tendons  of 
the  fingers. 

10.   The  Indicator, 

Is  a  small  muscle  on  the  back  of  the  ulna,  concealed  by  the 
extensor  communis  and  extensor  ulnaris.  It  arises,  tendinous 
and  fleshy,  from  the  back  of  the  ulna,  commencing  near  its  mid- 
dle, and  from  the  contiguous  part  of  the  interosseous  ligament. 
It  terminates  in  a  tendon  which  goes  through  the  same  fossa 
with  the  extensor  communis;  it  afterwards  is  joined  about  the 
head  of  the  first  phalanx  to  the  tendon  of  the  common  extensor 
belonging  to  the  fore  finger. 

With  the  tendon  of  the  extensor  communis,  it  is  inserted  along 
the  back  of  the  fore  finger  as  far  as  the  base  of  the  third  phalanx. 

It  extends  the  fore  finger.* 


SECT.  V. — OF  THE  MUSCLES  OF  THE  HAND. 

The  Palmaris  Brevis, 

Is  just  below  the  skin,  at  the  inner  side  of  the  palm  of  the 
hand.  It  consists  of  separate  fasciculi  unequally  divided,  and 
arises  from  the  anterior  ligament  of  the  wrist,  and  from  the  ul- 
nar  side  of  the  palmar  aponeurosis. 

It  is  inserted  into  the  skin  and  fat  at  the  inner  margin  of  the 
hand,  and  covers  the  muscles  of  the  little  finger. 

It  contracts  the  skin  of  the  hand. 


*  Varieties.  This  muscle  is  subject  to  many  modifications?  sometimes  it  is  di- 
gastric; sometimes  it  is  double,  and  the  second  head  goes  to  the  middle  finger.  In 
the  latter  case,  anatomists  have  recognised  a  disposition  similar  to  that  of  the  short 
extensors  of  the  toes,  and  also  an  arrangement  corresponding  with  what  occurs  in 
some  species  of  the  ape.  As  a  general  rule,  it  is  admitted  that  the  most  of  those 
varieties  in  the  muscular  system,  commonly  called  anomalies,  are  only  indications 
on  the  part  of  nature  of  the  alliance  between  the  structure  of  man,  and  that  of  the 
lower  orders  of  animals.  In  this  point  of  view,  they  are  both  instructive  and 
amusing,  and  are  well  deserving  of  attention. 


MUSCLES  OF  THE  HAND.  431 

Beneath  the  Aponeurosis  Palmaris  are  placed  the  long  flexor 
tendons,  and  many  of  the  small  muscles  of  the  hand. 


The  Lumbricales, 

Are  conspicuous ;  they  are  four  in  number,  of  the  size  and 
shape  of  earth  worms.  They  arise,  tendinous  and  fleshy,  from 
the  radial  sides  of  the  tendons  of  the  flexor  profundus,  beneath 
the  ligamentum  carpi  annulare  anterius,  and  a  little  beyond  its 
inferior  edge. 

They  terminate  in  little  flat  tendons,  which  run  along  the  outer 
or  radial  edge  of  the  fingers,  and  are  inserted  respectively  into 
the  tendinous  expansion  of  the  extensor  communis  on  the  back 
of  the  first  phalanx  of  each  finger,  about  its  middle. 

They  bend  the  first  phalanges.* 

Four  muscles  constitute  the  ball  of  the  thumb. 


1.   The  Abductor  Pollicis  Manus, 

Arises,  tendinous  and  fleshy,  from  the  anterior  surface  of  the 
ligamentum  carpi  annulare,  and  from  the  projecting  ends  of  the 
trapezium  and  scaphoides. 

It  is  inserted,  tendinous,  into  the  outer  side  of  the  base  of  the 
first  phalanx  of  the  thumb,  and  into  the  tendinous  membrane 
derived  from  the  extensors  on  its  back  part. 

It  draws  the  thumb  from  the  fore  fingers.  This  muscle  is 
next  to  the  skin. 

2.   The  Opponens  Pollicis , 

Is  beneath  the  abductor,  and  without  its  removal  can  scarcely 
be  seen.  It  arises,  tendinous  and  fleshy,  from  the  projecting 
point  of  the  os  trapezium,  and  from  the  adjacent  part  of  the  an- 
nular ligament. 

*  Varieties.  Sometimes  one  is  deficient?  sometimes  one  or  more  is  double,  in 
which  case  the  supernumerary  goes  to  the  ulnar  edge  of  the  adjoining  finger. 


432  MUSCLES. 

It  is  inserted,  tendinous  and  fleshy,  into  the  radial  edge  of 
the  metacarpal  bone  of  the  thumb,  from  its  base  to  its  head. 
It  draws  the  metacarpal  bone  inwards. 

3.   The  Flexor  Brevis  Pollicis  Manus, 

Is  beneath  the  abductor  pollicis,  and  at  the  side  of  the  oppo- 
nens  pollicis.  A  groove  is  formed  in  it  by  the  tendon  of  the 
flexor  iongus  pollicis,  which  divides  it  into  two  heads. 

The  first  head  arises,  fleshy,  from  the  points  of  the  trapezium, 
trapezoides,  and  from  the  contiguous  part  of  the  internal  sur- 
face of  the  annular  ligament,  and  is  inserted  into  the  outer  sesa- 
moid  bone ;  the  sesamoid  bone,  like  a  patella,  being  connected 
to  the  first  phalanx  of  the  thumb  by  a  tendon. 

The  second  or  internal  head  arises,  fleshy,  from  the  magnum 
and  unciforme,  near  their  metacarpal  surfaces,  and  from  the 
base  of  the  metacarpal  bone  of  the  middle  finger.  It  is  inserted 
into  the  inner  sesamoid  bone,  which,  like  the  external,  is  con- 
nected, by  ligament,  to  the  first  phalanx. 

The  short  flexor,  as  its  name  implies,  bends  the  first  phalanx 
of  the  thumb. 

4.  The  Adductor  Pollicis  Manus, 

Lies  in  the  palm  of  the  hand,  beneath  the  lumbricalcs  and 
the  tendons  of  the  flexor  sublimis  and  profundus.  It  arises, 
fleshy,  from  the  ulnar  edge  of  the  metacarpal  bone  of  the  mid- 
ble  finger,  between  its  base  and  head,  and  it  is  inserted,  tendi- 
nous, into  the  inner  part  of  the  base  of  the  first  phalanx  of  the 
thumb,  just  above  the  sesamoid  bone. 

It  pulls  the  thumb  towards  the  fingers. 

The  Abductor  Indicis  Manus, 

Is  on  the  radial  edge  of  the  hand,  between  the  metacarpal 
bones  of  the  fore  finger  and  thumb,  and  is  just  beneath  the  skin. 
It  arises  tendinous  from  the  trapezium,  and  fleshy  from  the  ul- 
nar edge  of  the  metacarpal  bone  of  the  thumb,  between  its  base 
and  head. 


MUSCLES  OF  TH&  HAND.  433 

Being  placed  along  the  side  of  the  metacarpal  bone  of  the 
fore  finger,  it  is  inserted,  by  a  short  tendon,  into  the  radial  side 
of  the  first  phalanx. 

It  draws  the  fore  finger  from  the  others. 

There  are  three  muscles  constituting  the  ball  of  the  ulnar  side 
of  the  hand,  or  of  the  little  finger. 


1.  The  Abductor  Minimi  Digiti  Manus, 

Is  the  most  superficial.  It  arises,  fleshy,  from  the  protube- 
rance on  the  internal  side  of  the  os  pisiforme,  and  from  the  con- 
tiguous part  of  the  annular  ligament. 

It  is  inserted,  tendinous,  into  the  ulnar  side  of  the  first  pha- 
lanx of  the  little  finger,  and  into  the  tendinous  membrane  which 
covers  its  back  part. 

It  draws  the  little  finger  from  the  rest. 

2.  The  Flexor  Parvus  Minimi  Digiti  Manus, 

Is  beneath  the  abductor.  It  arises,  fleshy,  from  the  unciform 
process  of  the  os  unciforme,  and  from  the  contiguous  part  of 
the  annular  ligament. 

It  is  inserted,  tendinous,  into  the  ulnar  side  of  the  base  of  the 
first  phalanx  of  the  little  finger,  being  united  with  the  tendon 
of  the  abductor,  and  with  the  tendinous  membrane  expanded 
over  the  back  of  the  finger. 

It  bends  the  little  finger.* 


o 


3.   The  Adductor  Metacarpi  Minimi  Digili, 

Is  placed  beneath  the  abductor  and  flexor,  next  to  the  meta- 
carpal bone.  It  arises,  fleshy,  from  the  unciform  process  of  the 
os  unciforme;  and  from  the  contiguous  part  of  the  annular  liga- 
ment of  the  wrist. 

It  is  inserted,  tendinous  and  fleshy,  into  the  fore  part  of  the 
metacarpal  bone  of  the  little  finger,  from  its  base  to  its  head. 

*  Varieties.     Sometimes  it  is  wanting-,  in  which  case  the  preceding  is  more 
developed  than  usual. 
VOL,  I.— 37 


434  MUSCLES. 

It  brings  the  metacarpal  bone  of  the  little  finger  towards  the 
wrist,  and  thereby  deepens  the  hollow  of  the  hand. 

The  Interosseous  Muscles  till  up  the  interstices  of  the  meta- 
carpal bones;  they  are  seven  in  number,  four  on  the  palm,  and 
three  on  the  back  of  the  hand.  The  back  ones  arise  by  double 
heads  from  the  contiguous  sides  of  two  metacarpal  bones;  the 
palmar  ones  have  a  single  head,  which  comes  only  from  the  meta- 
carpal bone  of  the  finger  which  the  interosseous  muscle  is  in- 
tended to  serve.  As  a  general  description,  they  all  may  be  said 
to  arise,  fleshy  and  tendinous,  from  the  base  and  sides  of  the  me- 
tacarpal bones,  and  to  be  inserted,  tendinous,  into  the  sides  of 
the  first  phalanges,  and  into  the  tendinous  membrane  on  the  back 
of  the  fingers,  derived  from  the  tendons  of  the  extensor  commu- 
nis.  The  first  four  must  be  looked  for  on  the  palm,  the  three 
others  on  the  back  of  the  hand. 


I.   The  Prior  Indicts, 

Is  along  the  radial  side  of  the  first  digital  metacarpal  bone, 
and  arises  from  the  base  and  side  of  the  same. 

It  is  inserted,  tendinous,  into  the  radial  side  of  the  first  pha- 
lanx of  the  fore  finger. 

It  draws  the  fore  finger  towards  the  thumb. 

2.  TTie  Posterior  Indicis, 

Is  at  the  ulnar  side  of  the  first  digital  metacarpal  bone.  It 
arises  from  the  base  and  ulnar  side  of  the  same  bone,  and  is  in- 
serted, tendinous,  into  the  ulnar  side  of  the  first  phalanx  of  the 
fore  finger. 

It  draws  the  fore  finger  towards  the  others. 

3.  The  Prior  Annularis, 

Is  at  the  radial  side  of  the  metacarpal  bone  of  the  third  or 
ring  finger.  It  arises  from  the  base  and  radial  side  of  the  said 
bone. 


MUSCLES  OF  THE  HAND.  435 

It  is  inserted,  tendinous,  into  the  radial  side  of  the  first  pha- 
lanx of  the  ring  finger. 

It  draws  that  finger  towards  the  thumb. 

4.   The  Interosseus  Digiti  Auricularis, 

Is  at  the  radial  side  of  the  metacarpal  bone  of  the  little  fin- 
ger, and  arises  from  the  radial  side  and  base  of  said  bone. 

It  is  inserted,  tendinous,  into  the  radial  side  of  the  first  pha- 
lanx of  the  same  finger* 

It  draws  the  little  finger  towards  the  other. 

By  removing  the  tendons  of  the  extensor  eommunis  from- 
the  back  of  the  hand,  we  see  the  three  posterior  or  double- 
beaded  interosseous  muscles* 

5.   The  Prior  Medii, 

Is  between  the  metacarpal  bone  of  the  fore  and  of  the  mid- 
dle finger.  It  arises  from  the  opposed  roots  and  sides  of  these 
bones. 

It  is  inserted,  tendinous,  into  the  radial  side  of  the  first  pha- 
lanx of  the  middle  finger. 

It  draws  the  middle  finger  towards  the  thumb, 

6,   The  Posterior  Medii, 

Is  between  the  metacarpal  bone  of  the  middle  and  of  the 
ring  finger.  It  arises  from  the  opposite  sides  and  roots  of  these 
bones. 

It  is  inserted,  tendinous,  into  the  ulnar  side  of  the  first  pha- 
lanx of  the  middle  finger. 

It  draws  the  middle  finger  towards  the  little. 

7.   The  Posterior  Annularis, 

Is  between  the  metacarpal  bones  of  the  ring  and  little  finger. 
It  arises  from  the  opposed  sides  and  roots  of  these  metiacarpal 
bones. 


436  FASCIA, 

It  is  inserted,  tendinous,  into  the  ulnar  side  of  the  first  pha- 
lanx of  the  ring  finger. 

It  draws  the  ring  towards  the  little  finger. 


CHAPTER  IV. 

OP  THE  FASCIAE  AND  MUSCLES  OF  THE  LOWER  EXTREMITIES. 
SECT.  I. OF  THE  FASCIJE. 

THE  muscles  of  the  lower  extremity,  from  the  pelvis  to  the 
foot  inclusively,  are  invested  by  a  strong  aponeurotic  mem- 
brane, placed  immediately  beneath  the  skin  or  common  integu- 
ments. Its  external  face  is  in  contact  with  the  superficial 
nerves  and  blood  vessels,  and  the  internal  face  with  the  muscles. 
Though  it  is  absolutely  continuous  from  one  end  to  the  other, 
it  will  be  useful,  for  study,  to  divide  it  into  three  parts;  the  one 
covering  the  thigh,  the  second  covering  the  leg,  and  the  third 
covering  the  foot;  as  each  of  them  presents  certain  points  of 
arrangement,  which  could  not  be  very  conveniently  introduced 
into  a  general  description. 

1.  The  aponeurosis  of  the  thigh  (Fascia  Lata  Femoris)  begins 
posteriorly,  from  the  upper  part  of  the  gluteus  magnus  mus- 
cle, by  a  very  gradual  conversion  of  the  cellular  membrane  of 
the  part  into  desmoid  substance;  it  also  begins  in  the  way  of 
cellular  substance  from  the  margin  of  the  sacrum  and  os  coc- 
cygis.  The  character  here  is  seldom  clearly  aponeurotic  till  it 
gets  on  a  level  with  the  tendon  of  the  gluteus  magnus,  from 
which  emanate  a  great  many  of  its  fibres.  Externally,  it  arises 
from  the  whole  length  of  the  crista  of  the  ilium,  is  there,  striking- 
ly aponeurotic,  and  is  closely  adherent  to  the  gluteus  medius 
muscle,  many  of  whose  fibres  arise  from  it.  It  also  arises  from 
the  body  and  rami  of  the  pubes,  and  from  the  tuber  and  ramus 
of  the  ischium.  Its  attachment  at  the  latter  is  not  very  strong* 


FASCIA  OF  THIGH.  437 

neither  is  its  character  so  well  marked.  It  is  there,  in  some 
measure,  continuous  with  the  perineal  fascia.  In  Front,  it  ad- 
heres very  closely  to  the  inferior  margin  of  the  tendon  of  the 
external  oblique  muscle,  so  as  to  be  almost  continuous  with  it, 
from  the  anterior  superior  spinous  process  of  the  ilium  to  the 
pubes. 

From  these  several  connexions  at  the  pelvis,  the  fascia  femo- 
ris  descends  in  enveloping  the  muscles  of  the  thigh,  and  then 
forms  other  strong  attachments  about  the  knee,  to  the  condyles 
of  the  os  femoris  and  to  the  head  of  the  tibia.  In  front,  it  ad- 
heres very  closely  to,  and  is  almost  blended  into  the  common 
tendon  of  the  extensor  muscles;  it  adheres,  also,  to  the  inferior 
margins  of  (he  two  vasti,  and  is  one  and  the  same  with  the 
membranous  expansion  (Invohicrum)  going  from  them  to  the 
head  of  the  tibia,  and  answering  the  purpose  of  capsular  liga- 
ment to  the  articulation  of  the  knee,  on  each  side  of  the  patella, 
as  far  back  as  the  lateral  ligaments.  Behind,  it  covers  up  the 
fat  in  the  ham,  and  is  continued  into  the  fascia  of  the  leg. 

The  fascia  femoris,  almost  every  where,  consists  in  a  fibrous 
texture,  which  is  sufficiently  evident,  but  the  fibres  pass  in  very 
various  directions.  At  many  places,  particularly  on  the  inter- 
nal side  of  the  thigh,  there  are  oblique  fibres  spread  upon  a  la- 
mina which  is  not  fibrous.  On  the  outside  of  the  thigh,  the  fas- 
cia consists  principally  in  longitudinal  fibres,  held  together  by 
transverse  ones;  and  when  its  interior  surface  is  examined, 
many  oblique  fibres  are  also  found  there.  It  is  very  thick  and 
strong  externally,  thinner  behind ;  and  still  weaker  internally, 
where  cellular  substance  seems  to  predominate  in  its  composi- 
tion. It  is  pierced  at  several  points  with  small  round  holes  for 
the  passing  of  blood  vessels  and  of  the  cutaneous  nerves. 

From  the  interior  surface  of  the  Fascia  Femoris,  partitions 
pass  off,  which  separate  the  muscles  of  the  thigh  from  each 
other,  and  form  sheaths  for  them.  Some  of  these  processes  are 
merely  cellular  substance;  others  have  a  more  distinct  desmoid 
character.  Externally,  as  it  passes  from  the  gluteus  medius  to 
the  groin,  it  separates  into  two  lamina?,  which  receive  between 
them  the  tensor  vaginae  femoris,  and  then  reunite.  The  sarto- 
rius  muscle,  in  almost  its  whole  length,  is  also  enclosed  between 
two  laminae.  At  the  origin  of  this  muscle,  the  posterior  lami- 
na passes  on  to  the  iiiacus  internus,  and  psoas  magnus  muscles, 

37* 


438  FASCIA* 

and  then  to  the  pectineus,  to  become  the  peotineal  fascia,  in  alF 
of  which  distance  it  is  continuous  with  the  iliac  fascia  of  the 
pelvis;  but  the  anterior  lamina  of  the  fascia  at  this  place  has  its 
upper  margin  continuous  with-Poupart's  ligament;  and  this  la- 
mina terminates  in  a  point  or  angle,  which  is  turned  inward  to 
the  crista  of  the  pubes,  and  ends  by  an  insertion  into  it  immedi- 
ately exterior  to  Gimbernat's  ligament,  and  in  the  same  line 
with  it.  This  point,  from  the  part  which  it  acts  in  femoral  her- 
nia, has  been  studied  with  particular  attention,  and  goes  under 
ihe  name  of  Key's,  or  the  Femoral  Ligament. 

The  Pectineal  fascia  is  placed  behind  the  femoral  vessels,  but 
the  sartorial  fascia  is  before  them.*  The  latter  terminates  on 
its  pubic  side,  in  a  crescentic  or  lunated  edge  of  one  and  a  half 
or  two  inches  in  length,  the  concavity  of  which  is  towards  the 
penis.f  Hey's  ligament  is  the  superior  extremity  of  the  cres- 
cent; the  inferior  end  can  scarcely  be  considered  to  have  a  de- 
finite boundary,  but  is  continuous  with  the  adjacent  part  of  the 
pectineal  fascia.  The  place  of  continuity  is  covered  by  the  sa- 
phena  vein,  which  being  between  the  skin  and  the  fascia  lata, 
dips  there  into  the  femoral  vein  which  is  under  the  crescentic 
edge.  The  femoral  vessels  reposing  in  their  sheaths,  are  then 
placed  between  these  laminoe  of  the  fascia  femoris.  The  vein 
is  only  partially  covered  by  the  lunated  edge,  while  the  artery, 
which  is  on  the  iliac  side  of  the  vein,  is  completely  concealed. 
By  keeping  the  leg  extended,  and  turning  the  toes  of  the  subject 
inwards  or  outwards,  it  will  be  seen  that  the  crescentic  edge 
and  the  tendon  of  the  external  oblique  exercise  a  mutual  ten- 
sion. Beneath  Poupart's  ligament,  at  the  inner  margin  of  the 
femoral  vein,  is  the  hole  called  the  Femoral  Ring,  through  which 
the  bowel  escapes  in  femoral  hernia.  This  hole  is  constricted 
by  turning  the  toes  outwards,  and  relaxed  by  turning  them  in- 
wards;, it  becomes  very  much  relaxed,  if,  at  the  same  time,  the 

*  By  sartorial  fascia  is  merely  meant  the  portion  of  the  fascia  luta  femoris  con- 
tiguous to  the  sartorius  muscle;  and,  by  pectineal  fascia,  the  part  covering-  the 
pectineus  muscle. 

f  The  crescentic  edge  is  not  always  well  defined,  for  in  many  cases  it  is  blend- 
ed insensibly  with  the  sheath  of  the  vessels,  so  that  a  defined  exhibition  of  it  is, 
l&thev  the.  result  of  artificial  separation  or  disseqtion.  than  a,  natural  condition,'. 


FASCIA  OF  LEG.  439 

thigh  be  drawn  upwards.  Valuable  indications  for  the  mode  of 
replacing  a  prolapsed  bowel  are  thus  obtained. 

In  addition  to  this  arrangement,  which  is  all-important  in 
hernia,  the  fascia  femoris  has  the  following.  On  the  front  of 
the  thigh  it  simply  covers  the  extensor  muscles,  the  partitions 
between  which  are  cellular  substance.  On  the  inner  side  it 
dips  down  to  the  periosteum  between  the  adductor  muscles,  but 
is  still  cellular.  Behind,  it  covers  the  ham-string  muscles,  and 
sends  down  to  the  linea  aspera  a  thick  fibrous  partition  be- 
tween the  vastus  externus  and  the  biceps  flexor. 

The  superior  margin  of  the  glutens  magnus  is  inserted  into 
this  fascia,  which  from  its  connexion  with  the  gluteus  medius 
ahd  tensor  vaginae  femoris,  causes  all  these  muscles  to  exercise 
a  mutual  influence,  as  well  as  to  keep  tense  the  fascia  itself. 
On  the  internal  semi-circumference  of  the  thigh  it  adheres 
somewhat  closely  to  the  muscles;  but  on  the  external,  where 
the  fascia  is  opposed  to  the  tendinous  facing  of  the  vastus  ex- 
ternus muscle,  it  is  connected  by  a  long,  loose,  and  scattered 
cellular  substance,  which  scarcely  presents  an  obstacle  to  the 
introduction  of  the  finger  or  any  blunt  instrument  between  the 
two. 

2.  The  Fascia  Cruralis,  or  that  of  the  Leg,  though  absolutely 
continuous  with  that  of  the  thigh,  may  be  described  as  arising 
externally,  from  the  head  of  the  fibula  and  from  a  prolongation 
of  the  biceps  flexor  cruris;  internally  from  prolongations  of  the 
tendons  of  the  sartorius,  the  gracilis,  and  the  semi-tendinosus. 
It,  in  descending,  covers  all  the  superficial  muscles  of  the  leg, 
does  not  go  over  the  tibia,  but  adheres  to  its  spine  and  to  its 
internal  angle.  It  unites  below  to  the  annular  ligament  of  the 
ankle,  to  the  ligamentous  sheath  of  the  peroneal  muscles,  and 
to  that  on  the  inner  ankle.  * 

The  fascia  cruralis,  in  the  superior  half  of  the  leg,  assists  in 
giving  origin  to  its  muscles  in  front  and  externally,  but  is  rather 
loosely  attached  to  them  below.  On  the  back  of  the  leg  it  is 
also  rather  loosely  connected  to  the  gastroenemii.  It  sends  in 
one  aponeurotic  partition  between  the  common  extensor  of  the 
toes  and  the  long  peroneus,  and  another  between  the  latter  and 
the  soleus,  both  of  which  are  inserted  into  the  fibula.  It  also 
is  insinuated  between  the_  soleus  and  the  flexor  muscles  next  to 


440  FASCIA. 

the  bones.  This  prolongation  is  strong  and  fibrous,  penetrates 
between  these  flexor  muscles,  dips  down  to  the  tibia  and  fibula, 
and  is  lost  insensibly  just  below  the  fascia  of  the  popliteus  mus- 
cle. The  popliteal  fascia  may  also  be  considered  one  of  the 
emanations  from  the  fascia  cruralis. 

The  fascia  cruralis  is  not  so  strong  as  the  femoral,  yet  it  has 
the  same  compact  desmoid  texture,  and  is  formed  from  fibres 
crossing  in  various  directions.  It  is  thicker  in  front  than  be- 
hind, and  is  made  tense  by  its  connexion  with  the  internal  and 
external  hamstring  muscles. 

Of  the.  Ligamentum  Annulare  of  the  Ankle  Joint. 

The  muscles  on  the  front  of  the  leg  have  their  tendons  con- 
fined at  the  ankle  by  this  ligament,  which  may  be  very  properly 
associated  with  the  description  of  the  crural  fascia,  owing  to 
the  closeness  of  their  connexion.  It  consists  in  a  fasciculus  of 
ligamentous  fibres  running  across  the  front  of  the  ankle  joint. 
It  is  attached  by  one  extremity  to  the  superior  face  of  the 
greater  apophysis  of  the  os  calcis,  just  before  the  rnalleolus  ex- 
ternus;  is  there  very  strikingly  fibrous  or  ligamentous,  and  has 
its  small  fasciculi  separated  by  fatty  matter.  It  is  then  direct- 
ed inwards,  and  divides  into  two  Iamina3,  one  of  which  goes 
above  the  tendons,  and  the  other  below  them.  These  lamina, 
by  adhering  to  their  respective  sides  of  the  tendons,  form  a 
loose  gutter  for  each  of  them  to  play  in;  the  gutters,  however, 
for  the  tibialis  anticus  and  extensor  pollicis  are  not  so  perfect 
behind  as  the  others,  and  are  also  more  loose.  The  ligament 
is  then  fixed  by  one  division  to  the  anterior  margin  of  the  mal- 
leolus  internus,  and  by  another,  which  is  wrapped  over  the  in- 
ternal face  of  the  foot,  into  the  scaphoides  and  the  internal 
margin  of  the  fascia  plantans.  As  the  upper  margin  of  this  lig- 
ament is  continuous  with  the  fascia  cruralis,  so  the  inferior 
runs  into  the  fascia  on  the  back  of  the  foot,  called  aponeurosis 
dorsalis  pedis. 

Of  the  FascicB  of  the  Foot. — The  fascia  cruralis,  being  strongly 
attached  to  the  posterior  and  lower  margins  of  the  internal  an- 
kle, its  fibres  radiate  thence  to  the  lower  part  of  the  tendo- 
achillis,  to  the  inner  side  of  the  os  calcis,  and  to  the  internal  mar- 


FASCIA  OF  FOOT.  441 

gin  of  the  fascia  plantaris.  This  is  the  Ligamentum  Laciniatum 
(or  plaited  ligament)  of  writers,  and  conceals  the  tendons 
which  pass  to  the  sole  of  the  foot,  along  the  sinuosity  of  the  os 
calcis. 

The  Aponeurosis  Dorsalis  is  continued  from  the  annular  liga- 
ment, over  the  upper  surface  of  the  foot,  to  the  roots  of  the  toes. 
It  is  thin,  but  its  fibrous  texture  is  apparent.  It  is  spread  over 
the  extensor  tendons  of  the  toes  and  the  extensor  brevis  muscle, 
and  is  slightly  attached  along  the  internal  and  the  external  mar- 
gin of  the  foot. 

The  Aponeurosis  Plantaris  is  on  the  sole  of  the  foot,  between 
its  common  integuments  and  the  muscles.  It  is  attached  be- 
hind to  the  tuberosities  of  the  os  calcis,  and  is  quickly  divided 
into  three  portions,  which  are  kept  distinct  by  well  marked  de- 
pressions between  them.  The  internal  portion  lies  upon  the 
muscles  at  the  inner  side  of  the  foot,  the  external  portion  upon 
the  muscles  at  the  outer  side,  and  the  middle  covers  longitudi- 
nally the  central  parts  of  the  sole.  The  first  two  portions  are 
thin,  reticulated,  and  extended  to  the  roots  of  the  outer  and  in- 
ner metatarsal  bones,  and  along  the  margins  of  the  foot,  where 
they  join  the  fascia  dorsalis.  The  middle  portion  increases  in 
breadth  as  it  advances,  and  at  the  anterior  extremity  of  the 
metatarsus  is  divided  into  five  slips,  one  for  each  metatarsal 
bone.  Each  of  these  slips  is  subdivided  into  two,  which  pene- 
trate upwards,  and  fix  themselves  to  their  respective  side  of 
the  head  of  the  corresponding  metatarsal  bone.  In  the  inter- 
val left  by  this  bifurcation,  pass  the  flexor  tendons,  the  lum- 
bricales,  the  vessels  and  the  nerves,  to  the  toe. 

The  plantar  aponeurosis,  or  fascia,  affords  behind,  origin  to 
the  superficial  muscles  of  the  sole  of  the  foot.  It  also  sends  in 
partitions  between  them.  Its  thickness  is  considerable  behind, 
but  continually  diminishes  as  it  advances  forwards.  Its  fibrous 
texture  is  very  well  marked,  and  is  much  more  compact  near 
the  heel,  where  it  looks  like  ligament;  the  fibres  run  principal- 
ly longitudinally.  From  its  inferior  surface  many  strong  fila- 
ments pass  to  the  skin  on  the  sole  of  the  foot,  and  contain  with- 
in their  interstices  a  granulated  adeps. 


442  MUSCLES. 


SECT.  II. — MUSCLES  OF  THE  THIGH. 

The  Tensor  Fascia  vel  Vagince  Femoris, 

Is  situated  superficially  on  the  anterior  outer  part  of  the  hip. 
It  arises,  tendinous,  from  the  anterior  superior  spinous  process 
of  the  ilium;  passes  downwards  and  somewhat  backwards  be- 
tween two  lamina?  of  the  fascia  femoris,  increasing  in  breadth 
as  it  descends;  and  is  inserted  fleshy  into  the  fascia  femoris, 
somewhat  below  the  level  of  the  trochanter  major. 

It  rotates  the  foot  inwards,  and  makes  the  fascia  tense. 


The  Sartorius, 

Is  placed  superficially  on  the  internal  side  of  the  thigh.  It 
arises  by  a  short  tendon  from  the  anterior  superior  spinous  pro- 
cess of  the  ilium,  and  passes  in  a  spiral  course  to  the  inner  side 
of  the  thigh  and  to  the  back  of  the  internal  condyle.  It  then 
winds  behind  the  head  of  the  tibia,  and  advances  forwards  so  as 
to  be  inserted  into  the  internal  side  of  the  lower  part  of  its  tu- 
bercle by  a  broad  tendon.  Its  fibres  run  the  whole  length  of 
the  muscle. 

Its  tendon  is  continued  by  a  flat  slip  from  its  lower  margin 
into  the  fascia  cruralis,  by  which  attachment  the  muscle  is  held 
in  its  spiral  course.  It  crosses  the  rectus  femoris  and  vastus  in- 
ternus  above,  the  triceps  adductor  at  the  middle  of  the  thigh, 
and  at  the  lower  part  of  the  latter,  just  above  the  knee,  it  is  be- 
tween the  tendon  of  the  adductor  magnus  and  that  of  the  gra- 
cilis. 

It  bends  the  leg  and  draws  it  obliquely  inwards.* 

The  Rectus  Femoris, 

Is  in  front  of  the  thigh  bone  and  just  beneath  the  fascia  femo- 
ris, with  the  exception  of  its  origin,  which  is  covered  by  the 

*  Varieties.  Sometimes  a  small  fasciculus  is  detached  from  its  inferior  part; 
sometimes  its  fibres  are  interrupted  by  a  middle  tendon  which  adheres  closely  to 
the  fascia  femoris.  Meckel  reports  it  as  deficient  in  one  case  that  he  met  with. 
In  the  African  I  have  occasionally  seen  it  unusually  broad. 


MUSCLES  OF  THE  THIGH.  443 

sartorius.  It  is  a  complete  penniform  muscle,  fleshy  in  front, 
for  the  most  part,  but  faced  behind  with  tendon.  It  arises  from 
the  anterior  inferior  spinous  process  of  the  ilium  by  a  round 
tendon,  which  is  joined  by  another  tendon,  coming  from  the 
superior  margin  of  the  acetabulum. 

It  is  inserted  into  the  superior  surface  of  the  patella  by  a 
strong  tendon,  and  intermediately  by  the  ligamentum  patellae 
into  the  tubercle  of  the  tibia. 

Its  extends  the  leg. 

The  Vastus  Exlernus, 

Is  a  very  large  muscle  on  the  outside  of  the  thigh ;  it  arises, 
tendinous  and  fleshy,  from  the  upper  part  of  the  os  fernoris,  im- 
mediately below  the  trochanter  major.  Its  origin  commences 
in  front,  and  passes  obliquely  around  the  bone  to  the  linea  as- 
pera.  It  continues  afterwards  to  arise  from  the  whole  length  of 
the  linea  aspera,  and  from  the  upper  half  of  the  line  running 
from  it  to  the  external  condyle. 

Its  fibres  pass  inwards  and  downwards,  and  are  inserted,  by 
a  flat  tendon,  into  the  external  edge  of  the  tendon  of  the  rectus, 
and  also  into  the  external  upper  part  of  the  patella.  This  mus- 
cle has  a  broad  tendinous  surface  exteriorly  and  above;  at  its 
lower  part  it  has  a  tendinous  facing  on  the  side  next  to  the  bone. 

It  also  extends  the  leg. 

The  Vastus  Internus, 

Covers  the  whole  inside  of  the  os  femoris.  It  arises,  by  a 
pointed  fleshy  origin,  in  front  of  the  os  femoris,  just  on  a  level 
with  the  trochanter  minor,  tendinous  and  fleshy  from  the  whole 
length  of  the  internal  edge  of  the  linea  aspera,  and  from  the  line 
leading  from  it  to  the  internal  condyle. 

Its  fibres  descend  obliquely,  and  are  inserted  by  a  flat  tendon 
into  the  internal  edge  of  the  tendon  of  the  rectus,  and  into  the 
upper  internal  edge  of  the  patella. 

It  also  extends  the  leg. 


444  MUSCLES. 


The  CrurcBus, 

Is  almost  completely  overlapped  and  concealed  by  the  two 
vasti,  and  is  immediately  behind  the  rectus  femoris.  The  edge 
of  the  vastus  externus,  above,  is  very  distinguishable  from  it,  as 
it  overlaps  it,  and  is  rounded  off,  besides  being  somewhat  sepa- 
rated by  vessels.  But  the  origin  of  the  vastus  internus  is  not 
so  distinguishable,  as  the  fibres  of  the  two  muscles  run  into  each 
other;  it  is,  therefore,  necessary,  most  frequently,  to  cut  through 
some  of  their  fibres  on  the  internal  face  of  the  os  femoris,  on  a 
level  with  the  trochanter  minor.  The  cruraeus  will  be  seen  to 
arise,  fleshy,  from  all  the  fore  part  of  the  bone,  and  from  all  its 
outside  as  far  as  the  linea  aspera.  Between  the  internal  edge 
of  this  muscle  and  the  linea  aspera,  the  interior  face  of  the  os 
femoris  is  free  or  unoccupied,  the  breadth  of  an  inch  along  the 
whole  shaft  of  the  bone,  which  is  very  readily  seen  by  turning 
off  the  vastus  internus. 

The  crurseus  is  inserted  into  the  posterior  face  of  the  tendon 
of  the  rectus  below,  and  into  the  upper  surface  of  the  patella. 

It  also  extends  the  leg. 

The  Ligamentum  Patellae  is  the  common  chord  by  which  the 
action  of  the  last  four  named  muscles  is  communicated  to  the 
tibia.  It  is  a  flattened  thick  tendon,  an  inch  and  a  half  wide, 
arising  from  the  inferior  edge  of  the  patella,  and  inserted  into 
the  tubercle  of  the  tibia.  Between  its  insertion  and  the  head 
of  the  tibia,  is  a  bursa.  Besides  this,  a  fascia  or  tendinous  ex- 
pansion, (Involucrum,)  an  appurtenance  of  the  fascia  femoris,  as 
mentioned  before,  comes  from  the  inferior  ends  of  these  mus- 
cles, extends  itself  over  the  whole  of  the  anterior  and  lateral 
parts  of  the  knee  joint,  and  is  inserted  into  the  head  of  the  tibia 
and  of  the  fibula.  Through  this  it  happens  that,  even  when 
the  patella  or  its  tendon  is  fractured,  some  motion  or  extension 
may  be  communicated  to  the  leg  from  the  thigh. 

In  consequence  of  the  common  insertion  of  these  four  mus- 
cles, some  anatomists  describe  them  as  but  one,  under  the  name 
of  Quadriceps  Femoris.* 

*  Scemmering  de  Corp.  Hum.  Fab. 


MUSCLES  OF  THE  THIGH.  445 

A  bursa  exists  between  the  lower  part  of  their  tendon  and 
the  fascia  femoris,  higher  up  than  the  patella;  occasionally,  one 
is  found  still  lower  down,  on  the  patella.* 


The  Gracilis, 

Is  a  beautiful  muscle  at  the  inner  margin  of  the  thigh,  and 
lies  immediately  under  the  fascia;  it  extends  from  the  pelvis  to 
the  leg. 

It  arises,  by  a  broad  thin  tendon,  from  the  front  of  the  os 
pubis,  just  at  the  lower  part  of  its  symphysis,  and  from  its  de- 
scending ramus;  the  muscle  tapers  to  a  point  below,  and,  a  lit- 
tle above  the  knee,  terminates  in  a  round  tendon,  which  passes 
behind  the  internal  condyle  of  the  os  femoris  and  the  head  of 
the  tibia.  It  then  makes  a 'curve  forwards  and  downwards  at 
the  internal  side  of  the  latter,  and  is  inserted  at  the  lateral  and 
inferior  part  of  its  tubercle. 

The  tendon  at  the  knee  is  beneath  the  tendon  of  the  sarto- 
rius.  This  muscle  is  a  flexor  of  the  leg. 

The  Pectinalis.  or  Pecti?ieus, 

Is  a  short,  fleshy  muscle,  at  the  inner  edge  of  the  psoas  mag- 
nus.  It  arises,  fleshy,  from  the  concavity  on  the  upper  face  of 
the  pubes,  between  the  linea  innominata,  and  the  ridge  above 
the  obturator  foramen,  and  is  inserted,  tendinous,  into  the  linea 
aspera,  immediately  below  the  trochanter  minor. 

It  draws  the  thigh  inwards  and  forwards/]* 


Adductors, 

1.  The  Adductor  Longus  comes,  by  a  rounded,  short  tendon, 
from  the  upper  front  part  of  the  pubes  near  its  symphysis;  it 
forms  a  triangular  belly  which  increases  in  breadth  in  its  de- 

*  Some  unimportant  varieties  have  been  observed  in  these  extensor  muscles. 

Varieties.  Sometimes  this  muscle  is  split  into  two  by  a  fissure,  in  which 
case  the  lower  portion  is  the  smaller,  and  has  its  tendon  below  connected  or 
joined  to  the  tendon  of  the  other,  and  its  other  extremity  attached  to  the  upper 
internal  margin  of  the  thyroid  foramen. 

VOL.  I.— 38 


446  MUSCLES. 

scent,  and  is  mserted  into  the  middle  third  of  the  linea  aspera 
at  its  inner  edge. 

As  the  subject  lies  on  its  back,  this  muscle  is  uppermost;  its 
origin  is  between  that  x>f  the  pectinalis,  and  of  the  gracilis;  its 
upper  edge  is  in  contact  with  the  lower  edge  of  the  pectinalis.* 

2.  The  Adductor  Brevis  is  the  smallest  of  the  three ;  it  is  situ- 
ated beneath  the  adductor  longus  and  pectinalis,  and  on  the  out- 
side of  the  gracilis.     It  arises,  by  a  rounded  tendon,  from  the 
middle  front  part  of  the  pubes,  between  its  symphysis  and  the 
foramen  thyroideum,  just  below  the  origin  of  the  first  adductor. 

It  is  inserted  into  the  upper  third  of  the  inner  edge  of  the  li- 
nea aspera,  between  the  trochanter  minor  and  the  upper  edge 
of  the  adductor  longus,  by  a  flat  thin  tendon.f 

3.  The  Adductor  Magnus  is  below  the  other  two,  and  is  by 
far  the  largest.     It  arises,  fleshy,  from  the  lower  part  of  the 
body  of  the  pubes  and  from  its  descending  ramus,  also  from  the 
ascending  ramus  of  the  ischium  as  far  as  its  tuberosity,  occupy- 
ing the  whole  bony  surface  between  the  foramen  thyroideum 
below,  and  the  margin  of  the  bone. 

It  is  inserted,  fleshy,  into  the  whole  length  of  the  linea  aspe- 
ra, and  on  its  internal  margin  a  tendon  is  gradually  generated 
which  passes  downwards  to  be  inserted  into  the  upper  part  of 
the  internal  condyle  of  the  os  femoris,  and,  by  a  thin  edge  or 
expansion,  into  the  line  leading  from  the  linea  aspera  to  the  in- 
ternal condyle. 

The  adductor  magnus  separates  the  muscles  on  the  anterior 
from  such  as  are  on  the  posterior  part  of  the  thigh ;  and  its  in- 
sertion is  closely  connected  with  the  origin  of  the  vastus  inter- 
nus,  the  two  surfaces  adhering  by  a  short  and  compact  cellular 
membrane. $ 

The  three  adductors  contribute  to  the  same  end,  that  of  draw- 

*  Varieties.  Occasionally  this  muscle  is  divided  into  two  by  a  fissure,  which 
is  of  various  lengths.  Sometimes  it  is  continued  much  lower  down  than  usual  by 
means  of  a  small  tendon  united  to  that  of  the  adductor  magnus. 

•f-  Varieties.  It  is  also  occasionally  split,  more  or  less  fully,  into  two  muscles 
by  a  fissure,  which,  according  to  Meckel,  establishes  a  remarkable  analogy  with 
apes. 

$  Varieties.    It  also  is  occasionally  divided  into  two  portions,  as  in  apes. 


MUSCLES  OF  THE  THIGH.  447 

ing  the  thigh  inwards.  From  their  common  action  and  very 
close  connexion  at  their  insertions,  they  are  sometimes  described 
as  one,  under  the  name  of  Triceps  Adductor,  and  with  great 
propriety.  The  pectineus  muscle  is  also  associated  with  them 
so  closely  in  its  course  and  character,  that,  as  Meckel  has  sug- 
gested, it  ought  to  be  considered  as  a  fourth  head  to  the  triceps. 


The  Glutceus  Magnus, 

Arises,  fleshy,  from  the  posterior  third  of  the  crista  of  the 
ilium,  from  the  side  of  the  sacrum  below  it,  from  the  side  of  the 
os  coccygis,  and  from  the  posterior  surface  of  the  large  sacro- 
sciatic  ligament.  The  fibres  of  this  muscle  are  collected  into 
large  fasciculi,  with  deep  interstices  between  them ;  and  the 
lower  edge  of  it  is  folded  over  the  sciatic  ligament.  . 

Its  fibres  pass  obliquely  forwards  and  downwards,  and  ter- 
minate in  a  thick,  broad  tendon,  the  upper  part  of  which  goes 
on  the  outside  of  the  trochanter  major,  and  is  very  strongly 
inserted  into  the  fascia  femoris;  while  the  lower  part  is  inserted 
into  the  upper  third  of  the  linea  aspera,  going  down  as  far  as 
the  origin  of  the  short  head  of  the  biceps  flexor  cruris. 

This  muscle  is  placed  immediately  under  the  skin,  the  fasci- 
culi being  separated  to  some  depth  by  processes  from  the  fascia 
femoris.  It  covers  nearly  all  the  other  muscles  on  the  back  part 
of  the  pelvis,  laps  over  its  inferior  margin  laterally,  and  conceals 
the  origins  of  the  ham-string  muscles. 

There  is  a  very  large  bursa  placed  between  the  tendon  of  this 
muscle  and  the  external  face  of  the  trochanter  major;  another 
of  almost  equal  magnitude,  between  it,  the  superior  extremity 
of  the  vastus  externus,  and  the  inferior  end  of  the  tensor  fasciae 
femoris;  and  there  are  two  smaller  ones  between  the  same  ten- 
don and  the  os  femoris,  which  are  placed  lower  and  more  pos- 
teriorly. 

The  glutaeus  magnus  draws  the  thigh  backwards,  and  assists 
in  keeping  the  trunk  erect. 


448  MUSCLES. 


The  Glutceus  Medius, 

Arises  from  the  whole  length  of  the  crista  of  the  ilium,  ex- 
cept its  posterior  third;  from  that  part  of  the  dorsum  of  the  bone 
which  is  between  its  crista  and  the  semicircular  ridge,  extend- 
ing from  the  anterior  superior  spinous  process  to  the  sciatic 
notch;  from  the  lunated  edge  of  the  os  ilium,  between  the  an- 
terior superior  and  the  anterior  inferior  spinous  process  ;  and 
from  that  part  of  the  inner  face  of  the  fascia  femoris  which  co- 
vers it. 

The  anterior  superior  part  of  this  muscle  is  not  covered  by 
the  glutaeus  magnus,  but  lies  before  it.  Its  fibres  converge,  and 
are  inserted,  by  a  broad  tbick  tendon,  into  the  upper  surface  of 
the  trochanter  major,  and  into  the  upper  anterior  part  of  the 
shaft  of  the  bone  just  in  front  of  the  trochanter. 

It  draws  the  thigh  backwards  and  outwards. 

A  bursa  is  interposed  between  the  extremity  of  its  tendon  and 
the  tendinous  insertions  of  the  small  rotator  muscles. 


The  GlutcBus  Minimus, 


Arises  from  that  part  of  the  dorsum  of  the  ilium  between  the 
semicircular  ridge  just  spoken  of,  and  the  margin  of  the  capsu- 
lar  ligament  of  the  hip  joint.  It  is  entirely  concealed  by  the 
glutaeus  medius. 

Its  fibres  converge  and  terminate  in  a  round  tendon,  which  is 
inserted  into  the  anterior  superior  part  of  the  trochanter  major, 
just  within  the  anterior  insertion  of  the  glutaeus  medius. 

It  abducts  the  thigh,  and  can  also  rotate  the  limb  inwards. 

A  bursa  of  small  size  exists  between  its  tendon  and  the  tro- 
chanter major. 

There  are  several  small  muscles  about  the  hip  joint,  the  most 
of  which  can  be  seen  by  the  removal  of  the  glutasus  magnus. 

The  Pyriformis, 

Arises,  fleshy  and  tendinous,  within  the  pelvis,  from  the  an- 
terior face  of  the  second,  third,  and  fourth  bones  of  the  sacrum. 


MUSCLES  OF  THE  THIGH.  449 

It  forms  a  conical  belly,  which  passes  out  of  the  pelvis  at  the 
upper  part  of  the  sacro-sciatic  foramen,  receiving  a  slip  of  fibres 
from  the  posterior  inferior  spinous  process  of  the  ilium. 

It  is  inserted,  by  a  round  tendon,  into  the  upper  middle  part 
of  the  trochnnter  major  within  the  insertion  of  the  glutaeus  me- 
dius. 

It  rotates  the  limb  outwards.  Between  its  tendon  and  the  su- 
perior geminus  a  small  bursa  exists.* 

The  Gemini, 

Are  two  small  muscles,  closely  connected  with  each  other, 
which  are  situated  lower  down  on  the  pelvis  than  the  pyrifor- 
mis.     The  upper  one  arises  from  the  posterior  part  of  the  root , 
of  the  spinous  process  of  the  ischium ;  the  lower  from  the  upper 
back  part  of  the  tuberosity  of  the  ischium. 

Being  parallel  to  each  other,  and  connected  by  their  conti- 
guous edges,  they  are  inserted  together  into  the  posterior  part 
of  the  thigh  bone  at  the  root  of  the  trochanter  major,  where  the 
deep  pit  is. 

They  also  rotate  the  limb  outwards.f 

The  Obturator  Inlernus, 

Is  principally  situated  within  the  cavity  of  the  pelvis.  It 
arises,  fleshy,  from  all  the  margin  of  the  foramen  thyroideum, 
except  where  the  obturator  vessels  go  out;  from  the  posterior 
face  of  the  ligamentous  membrane  stretched  across  it ;  also  from 
the  upper  part  of  the  plane  of  the  ischium  just  below  the  linea 
innominata;  its  fibres  converge,  and  forming  a  tendon,  pass  out 
of  the  pelvis  over  the  trochlea  of  the  ischium,  between  the  sa- 
cro-sciatic ligaments. 

The  tendon  is  placed  between  the  gemini  muscles,  which 
form  a  sheath  for  it;  and  it  is  inserted  into  the  pit  on  the  back 
of  the  os  femoris,  at  the  root  of  the  trochanter  major. 

*  Varieties.  It  is  sometimes  split  by  the  sciatic  nerve,  and  when  the  latter  di- 
vides very  high  up,  by  one  of  its  portions  only. 

•j-  Varieties.  The  upper  one,  occasionally,  does  not  exist,  whereby  a  striking 
resemblance  with  apes  is  established.  Sometimes  both  are  wanting. 

38* 


450  MUSCLES. 

Between  the  tendon  of  this  muscle  and  the  gemini  is  a  long 
bursa;  a  second  is  found  where  the  muscle  plays  over  the  is- 
chium. 

It  rotates  the  limb  outwards. 


The  Quadratus  Femoris, 

Is  lower  down  than  the  other  muscles.  It  arises,  tendinous 
and  fleshy,  on  the  outer  side  of  the  ischium,  from  the  ridge 
which  constitutes  the  exterior  boundary  of  the  tuberosity.  Its 
fibres  are  transverse,  and  are  inserted,  fleshy,  into  the  rough 
ridge  of  the  os  femoris,  on  its  back  part,  which  goes  from  one 
trochanter  to  the  other. 

It  rotates  the  limb  outwards.  A  bursa  exists  between  it  and 
the  trochanter  minor.* 


The  Obturator  Externus, 

Is  concealed,  in  front,  by  the  pectineus  and  triceps  adductor, 
and,  behind,  by  the  quadratus  femoris:  to  get  a  satisfactory 
view  of  it,  therefore,  these  muscles  should  be  detached  from  the 
bone.  It  arises  from  the  whole  anterior  circumference  of  the 
foramen  thyroideum,  excepting  the  place  where  the  obturator 
vessels  come  out,  and  from  the  anterior  face  of  the  ligamentous 
membrane  stretched  across  it. 

The  fibres  of  this  muscle  converge,  pass  beneath  the  capsu- 
lar  ligament  of  the  hip  joint  adhering  to  it,  and  terminate  suc- 
cessively in  a  round  tendon,  which  is  inserted  into  the  inferior 
part  of  the  cavity  on  the  posterior  surface  of  the  os  femoris,  at 
the  root  of  the  trochanter  major.  The  course  of  the  tendon  of 
this  muscle  is  marked  on  the  neck  of  the  thigh  bone  by  a  su- 
perficial fossa. 

It  rotates  the  thigh  outwards. 

*  Varieties.  Occasionally,  this  muscle  is  absent;  more  rarely  it  is  divided  into 
a  great  number  of  fasciculi,  amounting  in  one  instance  to  thirty. 


MUSCLES  OF  THE  THIGH.  451 

The  Sleeps  Flexor  Cruris, 

Constitutes  the  outer  hamstring,  and  is  situated  on  the  pos- 
terior outer  part  of  the  thigh;  it  arises  by  two  heads.  The 
first,  called  the  long  head,  has  an  origin,  in  common  with  the 
semi-tendinosus,  from  the  upper  back  part  of  the  tuberosity  of 
the  ischium,  by  a  short  tendon,  which,  in  its  descent,  is  changed 
into  a  thick  fleshy  belly.  The  other,  called  the  short  head, 
arises,  by  an  acute  fleshy  beginning,  from  the  linea  aspera  just 
below  the  insertion  of  the  glutaeus  magnus,  and  this  origin  is 
continued  along  the  lower  part  of  the  linea  aspera  and  from 
the  ridge  leading  to  the  external  condyle. 

A  thick  tendon  is  gradually  formed  on  the  outside  of  the 
muscle,  which,  descending  along  the  external  face  of  the  ex- 
ternal condyle,  is  inserted  into  the  superior  face  of  the  head  of 
the  fibula  at  its  point.  A  bursa  is  found  between  this  tendon 
and  the  external  lateral  ligament  of  the  knee. 

This  muscle  flexes  the  leg  on  the  thigru* 


,     T/i e  Se m iten dinosus, 

Is  on  the  inside  of  the  thigh,  between  the  biceps  andgracilis; 
it  is  superficial,  being  immediately  under  the  fascia,  and  arises, 
in  common  with  the  biceps,  from  the  back  part  of  the  tuberosi- 
ty of  the  ischium;  it  also  adheres,  for  three  or  four  inches,  to 
the  inner  edge  of  the  tendon  of  this  the  long  head  of  the 
biceps. 

About  four  inches  above  the  knee  it  terminates  in  a  long 
round  tendon,  which  passes  behind  the  internal  condyle  and 
the  head  of  the  tibia,  and  is  reflected  forwards  to  be  inserted 
into  the  side  of  the  tibia,  just  below  its  tubercle  and  very  near 
it,  being  lower  down  than  the  insertion  of  the' tendon  of  the 
gracilis.  Its  insertion  is  much  connected  with  that  of  the  gra- 

*  Varieties.  Sometimes  the  short  head  does  not  exist,  thereby  affording  an 
analogy  with  animals.  Sometimes  there  is  a  third  head,  but  more  delicate,  which 
comes  either  from  the  tuber  of  the  ischium  or  from  the  long  head,  and  descend- 
ing along  the  back  of  the  leg,  runs  into  the  tendo-aehillis,  corresponding  there- 
by with  the  arrangement  of  mammiferous  animals.. 


452  MUSCLES. 

cilis,  and  is  generally  divided  into  two  slips,  one  above  the 
other. 

Between  its  origin,  that  of  the  long  head  of  the  biceps,  and 
the  semimembranosus,  there  is  a  bursa :  one  or  more  are  like- 
wise found  between  its  tendon  below,  that  of  the  sartorius,  of 
the  gracilis,  and  the  internal  lateral  ligament  of  the  knee. 

It  flexes  the  leg  on  the  thigh.* 


The  Semimembranosus, 

Is  at  the  inner  side  of  the  thigh ;  its  upper  part  is  concealed 
by  the  semitendinosus  and  the  origin  of  the  long  head  of  the 
biceps,  and  below  it  projects  between  these  two  muscles.  It  is 
in  contact  with  the  posterior  surface  of  the  adductor  magnus. 

It  arises,  by  a  thick  round  tendon,  from  the  exterior  upper 
part  of  the  tuberosity  of  the  ischium,  which  tendon  soon  be- 
comes flattened,  and  sends  off  the  muscular  fibres  obliquely 
from  its  exterior  edge  to  a  corresponding  tendon  below.  The 
latter  passes  behind  the  internal  condyle  and  the  head  of  the 
tibia,  and  despatches  a  thin  aponeurotic  membrane  under  the 
inner  head  of  the  gastrocnemius,  to  cover  the  posterior  part  of 
the  capsule  of  the  knee  joint,  and  to  be  fastened  to  the  external 
condyle. 

It  is  inserted,  by  a  round  tendon,  into  the  inner  and  back 
part  of  the  head  of  the  tibia,  just  below  the  joint.  The  unfa- 
vourable insertion  of  this  muscle  is  compensated  for  by  the 
multitude  of  its  fibres,  which  gives  it  a  great  increase  of 
strength. 

A  bursa  exists  between  its  tendon  above  and  the  quadratus; 
another  exists  between  its  tendinous  termination,  the  internal 
head  of  the  gastrocnemius,  and  the  capsule  of  the  knee. 

It  flexes  the  leg  on  the  thigh. 


SECT.  III. MUSCLES  OF  THE  LEG. 

These  muscles  are  situated  anteriorly,  posteriorly,  and  ex- 
ternally. 

*  Varieties.    Sometimes  it  is  divided  into  three  sections  by  two  transverse 
tendinous  lines. 


MUSCLES  OF  THE  LEG.  453 


The  Tibialis  Anticus, 


Is  situated  superficially  under  the  fascia  of  the  leg,  at  the 
outside  of  the  spine  of  the  tibia,  and  in  front  of  the  interosseous 
ligament.  It  arises,  fleshy,  from  the  head  of  the  tibia,  from  its 
outer  surface,  spine,  and  from  the  interosseous  ligament  to 
within  three  or  four  inches  of  the  ankle.  It  also  arises,  by  its 
front  surface,  from  the  internal  face  of  the  fascia  of  the  leg. 

A  rounded  long  tendon  is  formed  in  front  below,  into  which 
the  fleshy  fibres  run  obliquely,  and  which,  passing  through  a 
distinct  noose  of  the  annular  ligament  in  front  of  the  malleolus 
internus,  crosses  the  astragalus  and  os  naviculare,  and  is  in- 
serted on  the  inner  side  of  the  sole  of  the  foot  into  the  anterior 
part  of  the  base  of  the  cuneiforme  internum,  and  into  tha  adja- 
cent part  of  the  metatarsal  bone  of  the  great  toe. 

A  bursa  surrounds  the  tendon  where  it  passes  beneath  the 
annular  ligament;  another  also  exists  at  its  lower  part. 

This  muscle  corresponds  with  the  radial  extensors  of  the 
arm. 

It  bends  the  foot,  and  presents  the  sole  obliquely  inwards. 

The  Extensor  Longus  Digitorum  Pedis, 

Is  also  superficially  placed  just  under  the  fascia  of  the  leg 
and  in  front  of  the  fibula,  being  in  contact  above  with  the  tibi- 
alis  anticus,  and 'below  with  the  extensor  proprius  pollicis.  It 
arises,  tendinous  and  fleshy,  from  the  outer  part  of  the  head  of 
the  tibia ;  from  the  head  of  the  fibula,  and  almost  the  whole 
length  of  its  anterior  angle;  also  from  the  upper  part  of  the 
interosseous  ligament  and  the  internal  face  of  the  fascia  of  the 
leg. 

Its  fibres  go  obliquely  downwards  and  forwards  to  the  ten- 
don which  begins  not  far  from  its  upper  end,  and  descends 
along  its  anterior  margin.  About  the  middle  of  the  leg  the  ten- 
don splits  into  four,  which  are  confined  by  the  annular  liga- 
ment of  the  ankle,  and  then  diverging,  each  is  inserted  into  the 
base  of  its  respective  toe,  the  big  excepted,  and  expanded  over 
its  back  part  as  far  as  the  last  phalanx. 

When  these  four  tendons  first  reach  the  roots  of  the  toes, 


454  MUSCLES. 

they  expand  over  the  back  of  the  articulation  there,  and  send 
downwards  triangular  processes  which  are  attached  to  the 
base  of  the  first  phalanx,  and  to  the  tendinous  terminations  of 
the  interosseous  muscles.  On  the  back  of  the  first  joint  the 
tendon  adheres  closely  to  its  synovial  membrane,  and  is  some- 
what cartilaginous.  At  ,the  second  joint  the  tendon  splits  par- 
tially into  two,  which  pass  somewhat  laterally,  and  then  re- 
unite. The  tendon  then  adheres  again  closely  to  the  synovial 
membrane  of  the  third  articulation,  and  finally  terminates  in 
the  base  of  the  third  phalanx. 

This  muscle  extends  the  toes,  but  flexes  the  foot. 

A  long  bursa  is  found  enveloping  the  tendons  where  they 
pass  beneath  the  annular  ligament  of  the  ankle. 

It  extends  all  the  joints  of  the  small  toes,  anxl  flexes  the  foot. 

The  Peroneus  Tertius, 

Is  rather  a  portion  of  the  extensor  longus,  is  found  at  its 
lower  outer  part,  and  cannot  be  naturally  separated  from  it.  It 
arises  from  the  anterior  angle  of  the  fibula,  between  its  middle 
and  lower  end. 

It  is  inserted,  by  a  flattened  tendon,  into  the  base  of  the  me- 
tatarsal  bone  of  the  little  toe,  and  assists  in  bending  the  foot. 

The  Extensor  Proprius  Pollicis  Pedis, 

Is  between  the  lower  part  of  the  tibialis  anticus,  and  of  the  ex- 
tensor longus.  It  arises  from  the  fibula  between  its  anterior 
and  internal  angles,  by  a  tendinous  and  fleshy  origin,  which 
commences  about  four  inches  below  the  head  of  the  fibula,  and 
continues  almost  to  its  inferior  extremity.  A  few  fibres  also 
come  from  the  interosseous  ligament,  and  from  the  lower  part 
of  the  tibia..  . 

The  muscle  being  half  penniform,  the  fibres  run  obliquely  to 
a  tendon  at  its  fore  part,  which  passes  through  a  particular  gut- 
ter of  the  annular  ligament,  and  over  the  astragalus  and  sca- 
phoides  and  upper  internal  parts  of  the  foot,  to  be  inserted  into 
the  base  of  the  first  and  second  phalanx  of  the  great  toe.  A 


MUSCLES  OF  THE  LEG.  455 

bursa  invests  this  tendon  where  it  passes  beneath  the  annular 

ligament. 

It  extends,  as  its  name  implies,  the  great  toe.* 

On  the  outside  of  the  leg,  between  the  fibula  and  fascia,  are 

the  two  Peronei  muscles. 


The  Peroneous  Longus,  sen  Primus, 

Arises,  tendinous  and  fleshy,  from  the  fore  and  outside  of 
the  head  of  the  fibula,  from  the  space  on  its  outer  side  above, 
between  the  external  and  anterior  angles;  also,  from  its  external 
angle  to  within  a  short  distance  of  the  ankle. 

A  flattened  thick  tendon,  to  which  the  fibres  pass  obliquely, 
constitutes  the  outer  face  of  the  muscle.  This  tendon  is  lodged 
in  the  groove  at  the  posterior  part  of  the  malleolus  externus, 
being  confined  to  it  by  a  thick  ligamentous  noose,  and  furnished 
there  with  a  bursa;  it  then  traverses  the  outer  side  of  the  os  cal- 
cis,  where  its  passage  is  marked  by  a  superficial  sulcus;  it  then 
runs  through  the  groove  of  the  os  cuboides,  where  there  is  ano- 
ther bursa.  Lying  deep  in  the  sole  of  the  foot,  covered  by  the 
calcaneo-cuboid  ligament,  and  next  to  the  tarsal  bones,  it  is  in- 
serted into  the  base  of  the  internal  cuneiform  bone,  and  into  the 
adjacent  part  of  the  metatarsal  bone  of  the  great  toe. 

It  extends  the  foot  and  inclines  the  sole  obliquely  outwards. 
It  corresponds  with  the  flexor  carpi  ulnaris  of  the  fore  arm. 

As  the  tendon  experiences  much  friction  at  the  ankle,  on  the 
os  calcis,  and  where  it  winds  around  the  os  cuboides,  it  is  not 
unusual  to  find  in  it  small  sesamoid  bones  there,  especially  at 
the  latter  place. 

The  Peroneus  Brevis,  sen  Secundust 

Is  concealed  in  a  great  degree  by  the  peroneus  longus,  being 
situated  between  the  latter  and  the  extensor  longus  digilorum. 
It  arises,  tendinous  and  fleshy,  from  the  outer  surface  of  the 
fibula,  commencing  about  one-third  of  the  length  of  the  bone 
from  its  head,  and  continuing  almost  to  the  ankle. 

Varieties.  A  partial  effort  is  sometimes  manifested  to  divide  it  into  two  mus- 
cles. 


456  MUSCLES. 

A  tendinous  facing  exists  externally  also  in  this  muscle,  to 
which  its  fibres  proceed  obliquely.  This  tendon  is  continued 
through  the  fossa  at  the  back  part  of  the  malleolus  externus,  be- 
ng  covered  by  the  tendon  of  the  peroneus  longus,  and  confined 
by  the  same  ligamentous  noose;  passing  through  the  superficial 
fossa  at  the  outer  side  of  the  os  calcis,  it  is  inserted  into  the  ex- 
ternal part  of  the  base  of  the  metatarsal  bone  of  the  little  toe. 

Jt  extends  the  foot,  and  presents  the  sole  obliquely  down- 
wards. It  corresponds  with  the  flexor  carpi  ulnaris.* 

Triceps  Surce. 

The  muscular  mass  on  the  back  of  the  leg,  constituting  its 
calf,  is  formed  by  the  two  following  muscles,  which,  with  much 
reason,  may  be  considered  as  composing  only  one.  Anatomists, 
who  view  them  in  this  latter  light,  describe  them  under  the 
name  of  Triceps  Sura?,  of  which  the  Gastrocnemius  portion  has 
two  heads,  and  the  Soleus,  or  Gastrocnemius  internus,  but  one. 

1.  The  Gastrocnemius  is  the  most  superficial  muscle  on  the 
back  of  the  leg,  and  conceals  the  other,  in  consequence  of  its 
breadth.     It  comes  from  the  condyles  of  the  os  femoris  by  two 
heads.     One  head  arises,  tendinous,  from  the  up-per  back  part  of 
the  internal  condyle,  and  fleshy  from  the  ridge  leading  to  the 
linea  aspera:  the  other  head  arises,  by  a  broad  tendon  in  the 
same  way,  from  the  external  condyle  and  the  ridge  above  it. 
A  triangular  vacancy  is  left  between  the  heads  of  the  muscle 
for  the  passage  of  the  popliteal  vessels;  the  heads  then  join  to- 
gether, but  in  such  a  way  that  the  appearance  of  two  bellies  is 
distinctly  preserved,  of  which  the  internal  is  the  largest.     The 
muscular  fibres  pass  from  a  broad  tendinous  facing  on  the  back 
to  a  corresponding  one  on  the  front  surface  of  the  muscle,  from 
the  latter  of  which  comes  the  tendo-achillis. 

2.  The  Soleus  is  beneath  the  Gastrocnemius,  and  arises,  fleshy, 
from  the  posterior  part  of  the  head  of  the  fibula,  and  from  the 
external  angle  of  that  bone,  for  two-thirds  of  its  length  down, 
behind  the  peroneus  longus.     It  also  arises,  fleshy,  from  the  ob- 

*  Varieties.     It  is  sometimes  double. 


MUSCLES  OF  THE  LEG.  457 

lique  ridge  on  the  posterior  surface  of  the  tibia,  just  at  the  lower 
edge  of  the  popliteus  muscle,  and  from  the  internal  angle  of  the 
tibia  for  four  or  five  inches.  The  two  origins  are  separated  for 
the  passage  of  the  posterior  tibial  vessels. 

The  body  of  this  muscle  has  a  great  intermixture  of  tendinous 
matter  in  it,  and  from  its  lower  extremity  proceeds  another 
origin  of  the  tendo-achillis.  About  three  or  foftr  inches  above 
the  heel,  this  tendon  joins  the  anterior  face  of  the  tendon  of  the 
gastrocnemius,  and  by  the  union  of  the  two  the  tendo-achillis 
is  completed,  and  then  inserted  into  the  posterior  surface  of  the 
os  calcis  near  its  tuberosities.  The  tendon  becomes  more  round 
as  it  descends. 

These  muscles  extend  the  foot,  and  are  all-important  in  walk- 
ing. A  bursa  is  between  their  tendon  and  the  os  calcis. 

'The  Plantaris, 

is  a  singular  little  muscle,  concealed  by  the  gastrocnemius, 
and  has  a  short  fleshy  belly  and  a  long  tendon.  It  arises,  fleshy, 
from  the  ridge  of  the  os  femoris,  just  above  the  external  eon- 
dyle,  passes  across  the  capsular  ligament  of  the  joint,  and  ad- 
heres to  it  in  its  course;  the  belly  terminates  somewhat  below 
the  head  of  the  tibia,  in  a  long,  delicate  tendon,  which  descends 
between  the  inner  part  of  the  soleus  and  the  gastrocnemius. 

At  the  place  where  the  tendons  of  these  unite,  the  tendon  of 
the  plantaris  emerges  from  between  them,  and,  running  at  the 
inner  edge  of  the  tendo-achillis,  is  inserted  into  the  inside  of  the 
os  calcis,  just  before  the  insertion  of  the  latter. 

It  extends  the  foot.  This  muscle  is  sometimes  wanting.  It 
contributes  so  little  to  the  motions  of  the  foot,  and,  in  other  re- 
spects, is  of  such  doubtful  use,  that  its  proper  destination  is  un- 
certain. In  some  mammiferous  animals  it  is  large  and  impor- 
tant; perhaps,  therefore,  in  the  human  subject,  it  is  one  of  the 
links  connecting  us  with  animals,  of  which  there  are  many  evi- 
dences in  the  muscular  system. 

The  Popliteus, 

Is  a  triangular  muscle  on  the  back  of  the  knee  joint.  It  arises, 
by  a  thick  round  tendon,  from  a  deep  depression  on  the  exte- 
VOL.  I.— 39 


458  MUSCLES. 

rior  face  of  the  external  condyle,  passes  through  the  capsular 
ligament,  being  connected  with  the  external  semi-lunar  carti- 
lage ;  and  then  forms  a  fleshy  belly  which  passes  obliquely  in- 
wards and  downwards. 

It  is  inserted,  fleshy,  into  the  oblique  ridge  on  the  back  of  the 
tibia,  just  below  its  head,  and  into  the  triangular  depression 
above  it.  A  bursa  exists  between  its  origin  and  the  capsular 
ligament ;  its  tendon  is  in  contact  with  the  synovial  membrane 
of  the  joint. 

It  bends  the  leg,  and  rotates  it  inwards,  when  bent. 


The  Flexor  Longus  Digitorum  Pedis  Perforans, 

Is  behind  the  tibia,  and  at  the  inner  edge  of  the  tibialis  pos- 
ticus.  It  arises,  by  an  acute,  tendinous  and  fleshy  beginning, 
from  the  back  of  the  tibia,  a  little  below  the  popliteus  muscle; 
its  origin  being  continued  along  the  internal  angle  of  the  tibia 
almost  to  the  ankle  joint.  It  arises,  also,  by  tendinous  and 
fleshy  fibres,  from  the  outer  edge  of  the  tibia,  just  above  its  con- 
nexion with  the  fibula  at  the  ankle:  the  latter  origin  is,  how- 
ever, frequently  deficient,  and  between  this  double  order  of 
fibres  the  tibialis  posticus  passes. 

The  fibres  go  obliquely  into  a  tendon  at  the  posterior  edge 
of  the  muscle,  which  runs  in  the  groove  behind  the  internal 
malleolus,  and  is  confined  there  by  a  strong  ligamentous  sheath, 
being  placed  behind,  and  within  the  tendon  of  the  tibialis  pos- 
ticus. The  tendon  then  gets  to  the  sole  of  the  foot  along  the 
sinuosity  of  the  os  calcis,  and  being  joined  by  a  considerable 
tendon,  detached  from  the  flexor  longus  pollicis,  it  divides  into 
four  branches  which  are  appropriated  to  the  four  smaller  toes. 

These  tendons  are  inserted  into  the  base  of  the  last  phalanges 
of  the  lesser  toes,  are  very  near  the  tarsal  bones,  and,  from  per- 
forating the  tendons  of  the  flexor  brevis,  correspond  with  the 
flexor  perforans  of  the  hand.  A  bursa  exists  where  the  tendon 
passes  along  the  tibia  and  the  os  calcis;  and  another  is  found  in 
the  sole  of  the  foot,  enveloping  this  tendon  and  that  of  the  flexor 
longus  pollicis. 

A  fifth  tendon  is  sometimes  observed,  which  splks  and  goes 


MUSCLES  OF  THE  LEG.  459 

to  the  second  bone  of  the  small  toe:  this  occurs  when  the  lat- 
ter is  not  supplied  from  the  flexor  brevis. 
This  muscle  flexes  the  small  toes,  and  extends  the  foot. 


The  Flexor  Longus  Pollicis  Pedis, 

Is  a  stout  muscle  formed  of  oblique  fibres,  and  situated  on  the 
back  part  of  the  fibula,  at  the  outer  side  of  the  tibialis  posticus. 
It  arises,  by  an  acute,  tendinous  and  fleshy  beginning,  from  the 
posterior  flat  surface  of  the  fibula,  commencing  about  three 
inches  from  its  head,  and  continuing  almost  to  the  ankle, 

The  tendon  of  this  muscle  is  large  and  round;  it  forms  gra- 
dually, and  constitutes  a  facing  to  the  posterior  edge  of  the  mus- 
cle. It  passes,  through  a  superficial  fossa  of  the  tibia,  at  the 
back  of  the  ankle  near  its  middle,  and  from  thence  through  a 
notch  in  the  back  edge  of  the  astragalus,  to  the  sole  of  the  foot; 
at  the  latter  place  it  crosses  the  tendon  of  the  flexor  longus  di- 
gitorum,  and  gives  off  to  it  the  branch  just  mentioned,  which 
goes,  principally,  to  the  second  toe.  This  tendon  is  deeper 
seated  in  the  foot  than  the  other. 

The  tendon  of  the  flexor  longus  pollicis  is  inserted  into  the 
last  phalanx  of  the  great  toe. 

It  bends  the  great  toe,  and  from  its  connexion  with  the  others 
will  bend  them  also.  A  bursa  invests  its  tendon  in  the  canal 
of  the  astragalus,  and  along  the  os  calcis;  another,  as  stated,  is 
common  to  it  and  the  last  muscle;  and  a  third  invests  the  ten- 
don along  the  metatarsal  bone,  and  the  first  phalanx  of  the  great 
toe.* 

The  Tibialis  Posticus, 

Is  placed  between,  and  concealed  by  the  last  two  muscles.  It 
arises  by  a  narrow  fleshy  beginning,  from  the  front  of  the  tibia, 
at  the  under  surface  of  the  process  which  joins  it  to  the  fibula, 
and  then  gets  to  the  back  of  the  leg  through  the  hole  in  the  up- 
per part  of  the  interosseous  ligament.  It  continues  its  origin 
from  the  whole  of  the  interosseous  ligament,  and  from  the  sur- 

*  The  variations  in  this  muscle  consist,  principally,  in  the  manner  of  distri- 
buting its  tendon  to  that  of  the  small  toes,  and  frequently  this  connexion  is  defi- 
cient. 


460  MUSCLES. 

laces  of  the  tibia  and  fibula  bordering  on  this  ligament,  except- 
ing one-third  of  the  lower  part  of  the  fibula,  and  rather  more  of 
the  lower  part  of  the  tibia. 

The  fleshy  fibres  run  obliquely  to  a  middle  tendon  which 
passes  in  the  groove  at  the  back  of  the  malleolus  internus,  and 
is  confined  there  by  a  fibro-cartilaginous  noose,  and  invested  by 
a  bursa.  It  is  inserted  into  the  posterior  internal  part  of  the  os 
naviculare  or  scaphoides,  at  its  tuberosity;  and  also  divides  in 
such  a  way  as  to  be  inserted  into  the  internal  and  external  cu- 
neiform bones,  into  the  os  cuboides,  and  os  calcis. 

It  extends  the  foot,  and  presents  the  sole  obliquely  inwards. 
It  corresponds  with  the  flexor  radialis  of  the  hand* 


SECT.  IV. OF  THE  MUSCLES  OF  THE  FOOT. 

The.  Extensor  Brevis  Digitorum  Pedis, 

Is  a  muscle  situated  on  the  superior  surface  of  the  foot.  It  is 
placed  beneath  the  tendons  of  the  extensor  longus,  and  arises, 
tendinous  and  fleshy,  from  the  fore  upper  part  of  the  greater 
apophysis  of  the  os  calcis,  being  intermixed  with  the  origin  of 
the  annular  ligament  of  the  ankle.  It  forms  a  short,  fleshy  bel- 
ly, which  is  partially  divided  into  four  parts;  from  these  parts 
proceed  as  many  tendons,  which  crossing  very  obliquely  the 
tendons  of  the  extensor  longus,  are  inserted  into  the  great  toe,, 
and  the  three  next  toes,  by  joining  with  the  tendons  of  the  ex- 
tensor longus,  which  are  spread  over  their  backs.  The  tendoa 
going  to  the  great  toe  has  its  principal  insertion  into  the  first 
phalanx. 

It  extends  the  toes.* 

When  the  Aponeurosis  Plantaris  is  removed  from  the  sole  of 
the  foot,  we  see  three  muscles;  the  middle  one  having  been  co- 
vered by  the  large  central  portion  of  the  aponeurosis,  is  the 
Flexor  Brevis  Digitorum  Pedis;  the  outer,  is  the  Abductor  Mi- 
nimi Digiti  Pedis;  and  the  inner,  the  Abductor  Pollicis  Pedis. 

*  Varieties.  The  internal  part,  or  belly,  is  sometimes  distinct  from  the  adjoin- 
ing. In  some  very  rare  cases  all  the  bellies  are  insulated,  as  in  birds.  Sometimes 
it  sends  a  tendon  to  the  little  toe. 


MUSCLES  OF  THE  FOOT.  461 

The,  Flexor  Brevis  Digilorum  Pedis, 

Arises,  fleshy,  from  the  large  tuberosity  of  the  os  calcis,  by  a 
narrow  beginning;  also  from  the  upper  surface  of  the  aponeu- 
rosis  plantaris,  and  the  tendinous  septa  between  it  and  the  con- 
tiguous muscles. 

It  forms  a  fleshy  belly,  going  nearly  as  far  forwards  as  the 
middle  of  the  metatarsal  bones ;  there  it  divides  into  four  tendons, 
which  go  to  the  four  smaller  toes..  These  are  perforated  by  the 
tendons  of  the  flexor  longus,  and  are  inserted  into  the  sides  of 
the  second  phalanges.  The  tendon  for  the  little  toe  is  often  de- 
ficient. 

It  bends  the  second  joint  of  the  toes. 

By  detaching  this  muscle  from  its  origin,  and  turning  it  down, 
we  bring  into  view  the  tendon  of  the  Flexor  Longus  Digitorum 
Pedis;  and  the  attachment  of  the  latter  to  the  tendinous  slip  from 
the  Flexor  Longus  Pollicis, — to  the  Massa  Carnea  Jacobi  Sylvii, 
or  Flexor  Accessorius, — and  to  the  Lumbricales  Muscles. 

The  Flexor  *flccessorius, 

Is  at  the  outside  of  the  tendon  of  the  flexor  longus.  It  arises, 
fleshy,  from  the  inside  of  the  sinuosity  of  the  os  ealcis,  and,  by 
a  thin  tendon,  from  the  outside  of  the  same  bone  before  its  tu- 
berosities. 

It  is  inserted,  fleshy,  into  the  outside  of  the  tendon  of  the  flexor 
longus,  just  at  its  division  into  four  tendons.  Like  a  second  hand 
to  a  rope,  it  assists  in  flexing  the  toes. 

The  Lumbricales  Pedis, 

Are  four  small  tapering  muscles,  which  arise  from  the  tendon 
of  the  flexor  longus,  just  after  its  division,  or  while  it  is  in  the 
act  of  dividing.  One  of  them  is  appropriated  to  each  lesser  toe, 
and  is  inserted  into  the  inside  of  its  first  phalanx,  and  into  the 
tendinous  expansion  that  is  sent  off  from  the  extensor  muscles  to 
cover  its  dorsum. 

They  increase  the  flexion  of  the  toes,  and  draw  them  inwards. 

39* 


462  MUSCLES. 

The  Mduclor  Polticis  Pedis, 

Arises,  tendinous  and  fleshy,  from  the  internal  anterior  part  of 
the  large  tuberosity  of  the  os  calcis;  from  a  ligament  being  a 
part  of  the  aponeurosis  of  the  sole  of  the  foot  extended  from  this 
tuberosity  to  the  sheath  of  the  tendon  of  the  tibialis  posticus; 
from  the  internal  side  of  the  naviculare,  and  from  the  cuneiforme 
internum. 

It  forms  the  internal  margin  of  the  sole  of  the  foot,  and  is  in- 
serted, tendinous,  into  the  internal  sesamoid  bone,  and  into  the 
base  of  the  first  phalanx  of  the  great  toe. 

It  draws  the  great  toe  from  the  rest. 

The  Flexor  Brevis  Pollicis  Pedis, 

Is  situated  immediately  at  the  exterior  edge  of  the  abductor 
pollicis.  It  consists  of  two  bellies,  which  are  parallel  with  each 
other,  and  separated  by  the  tendon  of. the  flexor  longus  pollicis; 
one  is  inseparably  connected  with  the  tendon  of  the  abductor 
pollicis,  and  the  other  with  the  adductor  pollicis  pedis. 

It  arises,  in  common  with  the  calcaneo-cuboid  ligament,  ten- 
dinous, from  the  under  part  of  the  os  calcis,  just  behind,  its  con- 
nexion with  the  os  cuboides,  and  from  the  under  part  of  the  ex- 
ternal cuneiform  bone. 

The  internal  belly  is  inserted,  tendinous,  into  the  internal  se- 
samoid bone,  along  with  the  tendon  of  the  abductor  pollicis,  and 
the  external  belly  is  inserted,  tendinous,  into  the  external  sesa- 
moid bone,  along  with  the  tendon  of  the  adductor  pollicis. 
Each  insertion  is  continued  to  the  base  of  the  first  phalanx  of 
the  great  toe. 

Jt  flexes  the  great  toe> 

The  Adductor  Pollicis  Pedis-, 

Is  situated  at  the  outside  of  the  flexor  brevis,  and  is  extended 
obliquely  across  the  metatarsal  bones.  It  arises,  tendinous,  at 
the  external  part  of  the  foot,  from  the  calcaneo-cuboid  ligament, 
and  from  the  roots  of  the  second,  third,  and  fourth  metalar.sa! 
bones... 


MUSCLES  OF  THE  FOOT.  463 

It  is  inserted,  tendinous,  into  the  external  sesamoid  bone, 
which  insertion  is  continued  to  the  first  phalanx  of  the  great 
toe,  and  is  closely  united  to  the  tendon  of  the  external  head  of 
the  flexor  brevis  pollicis, 

It  draws  the  great  toe  towards  the  others. 


The  Mductor  Minimi  Digiti  Pedis, 

Forms  the  external  margin  of  the  sole  of  the  foot,  and  is  im- 
mediately beneath  the  aponeurosis  plantaris.  It  arises,  tendi- 
nous and  fleshy,  from  the  outer  tuberosity  of  the  os  calcis,  and 
also  from  the  exterior  part  of  the  base  of  the  metatarsal  bone  of 
the  little  toe. 

It  is  inserted,  by  a  rounded  tendon,  into  the  exterior  part  of 
the  base  of  the  first  phalanx  of  the  little  toe. 

It  draws  the  little  toe  from  the  other  toes. 


The  Flexor  Brevis  Minimi  Digiti  Pedis, 

Is  just  within  the  tendon  of  the  abductor  minimi  digiti.  It 
arises  from  the  calcaneo-cuboid  ligament  as  extended  from 
the  tuberosity  of  the  cuboid  bone  to  the  heads  of  the  two  outer 
metatarsal  bones;  also  from  the  root  of  the  outer  or  fifth  meta- 
tarsal bone. 

It  is  inserted,  by  a  tendon,  into  the  lower  part  of  the  first  pha- 
lanx of  the  little  toe,  at  its  base,  and  into  the  head  of  the  meta-- 
tarsal  bone  of  the  same  toe. 

It  bends  the  little  toe. 


The  Transfer  salis  Pedis  $ 

Is  placed  beneath  the  tendons  of  the  flexor  muscles.*  It  is 
small,  and  lies  across  the  anterior  extremities  of  the  metatarsal 
bones.  It  arises,  tendinous,  from  the  capsular  ligament  of  the 
first  joint  of  the  little  toe;  it  also  arises  from  the  capsular  liga- 
ment of  the  first  joint  of  the  next  toe. 

I.t  is  inserted  into  the  exterior  face  of  the  common  tendon  oC 

*  The  sole  is  presumed  to  be  upwards. 


i 
464  MUSCLES. 

the  adductor  and  the  flexor  brevis  pollicis,  at  the  external  sesa- 
moid  bone. 
It  approximates  the  heads  of  the  metatarsal  bones. 

The  Interosseous  Muscles  are  seven  in  number,  four  of  which 
may  be  seen  on  the  upper  surface  of  the  foot.  There  are  two 
to  the  first  smaller  toe,  two  to  the  second,  two  to  the  third,  and 
one  to'  the  fourth,  or  little  toe.  The  muscles  seen  on  the  upper 
side  of  the  foot  are  double-headed,  that  is,  they  arise  from  the 
contiguous  surfaces  of  the  metatarsal  bones. 

The  Interosseus  Primus,  Digiti  Primi  Pedis,  or  the  Jlbductor 
Indicts  Pedis, 

Is  seen  superiorly.  It  is  placed  between  the  metatarsal  bone 
of  the  great  toe,  and  the  first  small  toe,  and  arises,  fleshy,  by  a 
double  head,  from  the  opposed  surfaces  of  their  roots  and  bodies. 

It  is  inserted,  tendinous,  into  the  inside  of  the  root  of  the  first 
joint  of  the  first  small  toe,  and  pulls  it  inwards. 

The  Interosseus  Secundus,  Digiti  Primi,  or  the  Adductor  Indicis 

Pedis, 

Is  also  external  or  above.  It  is  situated  between  the  meta- 
tarsal bones  of  the  first  and  second  small  toes,  arising  from  the 
opposed  surfaces  of  their  roots  and  bodies  by  a  double,  fleshy, 
and  tendinous  head. 

It  is  inserted  into  the  outside  of  the  first  phalanx  of  the  same 
toe,  by  a  tendon. 

It  draws  this  toe  outwards. 

The  Interosseus  Secundus,  Digiti  Secundi,  or  the  Adductor 
Medii  Digiti, 

Is  seen  at  the  upper  part  of  the  foot,  betvveen  the  second  and 
third  metatarsal  bones  of  the  lesser  toes,  arising  from  the  oppo- 
site surfaces  of  their  roots  and  bodies. 

It  is  inserted,  tendinous,  into  the  outside  of  the  base  of  the 
first  phalanx  of  the  second  small  toe. 

It  draws  this  toe  outwards. 


MUSCLES  OF  THE  FOOT.         .  465 


The  Interosseus  Secundus,  Digiti  Tertii,  or  the  Adductor  Tertii 

Digiti, 

Is  seen  on  the  upper  surface  of  the  foot,  occupying  the  inter- 
val of  the  metatarsal  bones  of  the  third  and  fourth  small  toes, 
and  arises,  by  a  double  head,  from  the  opposite  surfaces  of  their 
roots  and  bodies. 

It  is  inserted,  tendinous,  into  4he  outside  of  the  root  of  the 
first  phalanx  of  the  third  small  toe. 

It  draws  this  toe  outwards. 


The  Interosseus  Primus,  Digiti  Secundi  Pedis,  or  the  Abductor 
Medii  Digiti, 

Is  at  the  bottom  of  the  foot,  and  arises  from  the  inside  of  the 
metatarsal  bone  of  the  second  smaller  toe. 

It  is  inserted  into  the  inside  of  the  first  phalanx  of  the  second 
toe. 

It  draws  this  toe  inwards. 

The  Interosseus  Primus,  Digiti  Tertiit  or  the  Abductor  Tertii 

Digiti, 

Is  in  the  sole  of  the  foot.  It  arises  from  the  inside  of  the  me- 
tatarsal bone  of  the  third  smaller  toe,  beginning  near  its  root, 
and  is. inserted,  tendinous,  into  the  inside  of  the  base  of  the  first 
phalanx  of  the  same  toe. 

It  draws  this  toe  inwards. 


The  Interosseus  seu  Adductor,  Digiti  Minimi, 

Is  on  the  under  surface  of  the  foot.  It  arises  from  the  inside 
of  the  base  and  body  of  the  metatarsal  bone  of  the  fourth  small, 
or  the  little  toe,  and  is  inserted,  tendinous,  into  the  inside  of  the 
first  phalanx  of  the  little  toe. 

It  draws  this  toe  inwards. 


BOOK  IV. 


OF  THE  ORGANS  OF  DIGESTION. 

THE  organs  of  digestion  consist  in  an  uninterrupted  canal  ex- 
tending from  the  lips  to  the  anus;  and  of  numerous  glandular 
bodies  placed  all  along  its  track,  for  pouring  their  secretions 
into  it. 

This  canal,  called  Alimentary,  (Ductus  Cibarius,)  is  in  three 
principal  portions:  the  superior,  the  middle,  and  the  inferior  or 
terminating.  The  superior  portion  is  composed  of  the  mouth, 
the  pharynx,  and  the  oesophagus.  The  middle,  of  the  stomach 
and  small  intestine.  And  the  inferior,  of  the  large  intestine. 

The  glandular  organs  are  the  salivary  glands,  the  pancreas, 
the  liver,  the  spleen,  and  an  extremely  numerous  set  of  mu- 
ciparous  glands,  extending  from  one  end  to  the  other  of  the 
canal. 

The  organs  of  digestion  may  be  divided,  according  to  their 
physical  functions,  into  those  of  mastication  and  deglutition,  and 
into  those  of  assimilation. 


BOOK    IV. 


PART    I. 

Organs  of  Mastication  and  Deglutition. 
CHAPTER  I. 

OF  THE  MOUTH. 

THE  Mouth  (Cavum  Oris)  occupies  the  space  in  the  inferior 
part  of  the  face,  between  the  upper  and  the  lower  jaw.  It  is 
separated  from  the  nose  by  the  palatine  processes  of  the  supe- 
rior maxillary  and  palate  bones,  and  by  the  soft  palate,  which 
is  continued  backwards  from  them.  It  extends  from  the  lips, 
in  front,  to  the  soft  palate  and  pharynx  behind,  and  its  floor  is 
formed  by  the  mylo-hyoid  muscles. 

The  anterior  and  lateral  periphery  of  the  mouth  is  constituted 
by  the  muscles  of  the  lips  and  cheeks,  covered  externally  by 
common  skin,  and  internally  by  the  lining  membrane  of  the 
mouth.  The  cavity  of  the  latter  is  divided  into  two  portions, 
by  the  projection  of  the  teeth  and  of  the  alveolar  processes  of 
the  upper  and  under  jaws;  these  two  portions,  when  the  teeth 
are  complete,  are  separated  from  each  other  while  the  mouth 
is  closed.  The  anterior  portion,  which  is  sometimes  called  the 
vestibule  of  the  mouth,  varies  its  size  very  considerably  in 
mastication,  and  has  its  parietes  extremely  moveable.  The  ca- 
paciousness of  the  posterior  admits  also  of  much  change,  by  the 
motions  of  the  tongue  and  by.  the  depression  of  the  lower  jaw. 

The  whole  cavity  of  the  mouth  is  lined  by  a  membrane,  con- 
tinued over  the  lips  from  the  skin,  and,  in  many  respects,  strong- 
ly resembling  the  texture  of  the  latter;  it  is,  however,  much 

VOL.  I.-— 40 


470  ORGANS  OF  DIGESTION. 

finer;  is  furnished  every  where  with  an  epidermis;  is  very  vas- 
cular, and  has  beneath  it  a  great  number  of  muciparous  glands. 
Its  texture  undergoes  some  changes,  according  to  its  position, 
upon  the  lips  and  cheeks,  upon  the  gums  and  palate,  and  upon 
the  tongue ;  all  of  which  will  be  explained  in  due  season. 

This  lining  membrane  of  the  mouth,  for  the  most  part  thin 
and  very  flexible,  forms,  at  several  points,  folds  or  duplicatures. 
Four  of  them  are  situated  on  the  middle  line  of  the  body,  and 
are  called  frenula:  one  goes  from  the  posterior  face  of  the  upper 
lip  to  the  middle  palate  suture  in  front  of  the  central  alveolar 
processes  of  the  upper  jaw ;  a  second  goes  from  the  posterior 
face  of  the  lower  lip  to  the  front  of  the  symphysis  of  the  lower 
jaw;  a  third  goes  from  the  under  part  of  the  tongue  to  the  pos- 
terior face  of  the  symphysis  of  the  lower  jaw,  (frcenulum  lin~ 
guce ;)  and  the  fourth  goes  from  the  front  of  the  epiglottis  carti- 
lage to  the  middle  of  the  root  of  the  tongue.  Besides  these, 
there  are  some  other  duplications,  which  wilt  be  mentioned  in 
their  proper  order. 

The  lips  (Labia)  are  always  somewhat  thicker  at  their  loose 
margins  than  elsewhere;  the  skin  which  covers  them  there,  is 
remarkable  for  its  vascularity,  and  changes  its  texture  insensi- 
bly, as  it  is  continued  from  the  face  to  the  lining  membrane  of 
the  mouth. 

The  upper  lip  is  longer  and  thicker  than  the  lower,  is  some- 
what pointed  in  the  centre,  and  has  on  its  front  surface  a  ver- 
tical depression,  (philtrum,)  beginning  at  the  septum  of  the  nose 
and  going  downwards  to  the  centre  of  the  lip.  This  depression 
is  the  remains  of  a  fissure  which  always  exists  between  the  two 
halves  of  the  lip,  in  the  early  foetal  or  forming  stage.  The 
junction  of  the  extremities  of  the  lips  constitutes  the  corners  of 
the  mouth  (anguli  oris.) 

The  lips  are  composed  of  muscular  fibres,  much  blended  with 
adipose  matter.  The  muscles  which  concur  to  form  them  are 
the  orbicularis  oris  and  the  buccinators ;  besides  which,  the  up- 
per lip  is  furnished  on  each  side  with  the  two  levators,  with  the 
depressor,  and  the  zygomatici ;  while  the  lower  lip  has  its  two 
depressors  and  a  Jevator.  See  muscles  of  the  face. 


OF  THE  TEETH.  471 


CHAPTER    II. 


OF  THE  TEETH. 

THE  Teeth  (Denies)  are  by  far  the  hardest  portions  of  the 
human  fabric ;  and  though  they  bear  in  their  composition  and 
appearance  a  strong  analogy  with  bone,  yet  they  diner  from  it 
in  their  more  limited  duration,  their  mode  of  development, 
their  partial  nudity,  their  nutrition,  and  in  the  manner  by  which 
they  are  united  to  the  body. 

The  greater  part  of  the  length  of  each  tooth  is  implanted 
into  the  alveolar  process  of  the  jaw,  and  the  part  so  fixed  is 
technically  called  the  root;  immediately  beyond  this  a  small 
portion  of  the  tooth  is  embraced  by  the  gum;  this  is  the  neck; 
and  the  free,  or  projecting  'part  of  the  tooth  covered  with  a 
shining  porcelain  like  layer  called  the  enamel,  is  its  body. 


SECTION  I. 

The  whole  number  of  teeth  in  the  adult  is  thirty-two,  sixteen 
in  each  jaw,  and,  when  healthy,  they  are  all  fixed  with  so  much 
firmness  by  the  gomphosis  articulation,  that  the  very  slight  de- 
gree of  motion,  which,  by  force,  they  may  be  caused  to  exe- 
cute, is  scarcely  perceptible.  The  differences  existing  in  their 
shape,  have  caused  anatomists  to  classify  them  accordingly; 
on  each  side  of  the  middle  line  of  each  jaw  there  are  two  Inci- 
sors, one  Cuspated,  two  Bicuspated,  and  three  Molar  teeth. 
There  are  also  some  peculiarities,  as  they  belong  to  the  upper 
or  to  the  lower  jaw;  but  they  correspond  exactly  with  their 
fellows  on  the  opposite  side  of  the  same  jaw. 

The  Incisors  (Denies  Incisivi)  are  next  to  the  middle  line, 
and  are  named  from  their  being  brought  to  a  straight  cutting 
edge,  like  a  chisel,  by  being  bevelled  from  behind.  They  are 
somewhat  convex  on  their  anterior  faces,  but  behind  they  are 


472  ORGANS  OF  DIGESTION. 

very  concave:  owing  to  their  thinness  for  some  distance  from 
the  cutting  edge,  they  are  apt  to  be  broken.  In  early  life,  their 
cutting  edge  is  slightly  serrated.  They  have  each  but  one 
root,  which  is  conoidal,  terminates  by  a  sharp  point,  and  is  not 
unfrequently  impressed  longitudinally  on  each  side  by  a  super- 
ficial furrow. 

The  central  incisors  of  the  upper  jaw  are  broader  and  longer 
than  the  outer  ones ;  the  anterior  face  of  the  latter  is  more  con- 
vex, and  their  cutting  edge  more  rounded.  The  incisors  of  the 
lower  jaw  are  much  narrower  than  those  of  the  upper,  and 
have  their  roots  flattened  on  the  sides;  they  do  not  differ  essen- 
tially among  themselves,  except  that  the  external  ones  are  some- 
what wider  than  the  internal. 

The  enamel  of  the  incisors  is  continued  farther  down,  and  is 
thicker  on  their  anterior  and  posterior  surfaces  than  laterally; 
it  is  also  thicker  on  the  front  than  on  the  back  part.* 

The  Cuspated  Teeth  (Denies  Cuspidati,  Canini,)  are  next  to 
the  incisors,  one  on  each  side.  Their  body  is  conoidal,  and  is 
brought  to  a  sharp  point  at  its  summit;  the  principal  obliquity 
in  effecting  the  latter,  being  on  the  side  of  the  interior  of  the 
mouth.  They  are  more  convex  externally,  than  the  incisors, 
but  not  so  concave  internally,  they  are  also  thicker  and  more 
cylindroid.  They  have  each  but  one  root,  which  is  conoidal, 
and  which,  as  also  the  body,  is  longer  than  the  corresponding 
portion  of  any  of  the  other  teeth.  They  stand  nearly  perpen- 
dicularly, and  are  more  covered  on  their  sides  with  enamel 
than  the  incisors. 

The  cuspated  teeth  of  the  upper  jaw  have  longer  roots  than 
those  of  the  lower,  and  are  called,  in  common  language,  eye- 
teeth  :  those  of  the  lower  jaw  sometimes  are  called  stomach- 
teeth. 

The  Bicuspated  Teeth  (Denies  Bicuspidati,)  two  in  number 
on  each  side,  are  situated  behind  the  cuspate;  they  are  also 
called  small  molar.  They  are  almost  precisely  alike,  with  the 
exception  that  the  first  is  smaller  than  the  other,  and  resembles 
rather  more  the  type  of  the  cuspidatus  than  the  second  does. 

*  Natural  History  of  the  Human  Teeth,  by  J.  Hunter,  London,  1778. 


OF  THE  TEETH.  .      473 


Their  body  is  very  nearly  cylindrical,  being  flattened,  however, 
on  the  faces  next  to  adjoining  teeth.  The  masticating  surface 
of  the  body  is  formed  into  two  points,  whence  the  name ;  one 
external,  and  the  other  internal:  the  former  is  the  longest  and 
thickest,  and,  consequently,  the  most  conspicuous.  The  ena- 
mel forms  an  almost  circular  crown,  covering  the  projecting 
parts  of  these  teeth.  The  root  of  each  one  is  single,  but  has  a 
deep  and  well  marked  fossa  on  each  side  running  its  whole 
length,  and  presenting  the  semblance  of  an  effort  at  duplicity; 
it  is  also  conoidal,  and  sometimes  in  the  upper  jaw  bifurcated 
at  its  end. 

The  bicuspate  teeth  of  the  upper  and  of  the  lower  jaw  re- 
semble each  other  so  strongly  that  the  difference  between  them 
is  not  striking;  it  is,  however,  determined  by  those  of  the  up- 
per jaw  being  rather  more  voluminous  and  ovoidal  in  their  bo- 
dies, and  having  rather  longer  and  larger  roots. 

The  Molar  Teeth,  (Denies  Molares,)  three  in  number,  on  each 
side,  succeed  the  bicuspated.  They  are  well  characterized  by 
their  greater  size.  Their  bodies  are  almost  cuboidal,  with 
rounded  angles,  and  are  protected  with  a  circular  crown  of 
enamel;  their  grinding  surface  has  five  points,  three  externally, 
and  two  internally:  the  rule,  however,  is  not  uniform,  as  they 
frequently  have  only  four,  and  sometimes  in  the  upper  jaw  only 
three  points. 

The  first  molar  is  the  largest  of  any,  and  very  generally  has 
five  points,  in  the  upper  jaw  it  has  three  roots,  two  of  which 
are  outward,  and  the  other  inward;  but  in. the  lower  jaw  it  has 
only  two  roots,  one  before  the  other. 

The  second  molar  of  each  jaw,  with  the  exception  of  its  being 
smaller  than  the  first,  presents  no  essential  difference  from  it, 
either  in  regard  to  its  body  or  roots.  The  fifth  point  is  some- 
times not  so  well  developed. 

The  third  molar  resembles  the  other  two  in  its  body,  but  is 
smaller  than  either  of  them.  Most  frequently  its  roots,  instead 
of  diverging  from  each  other  and  standing  out  distinctly,  are 
imperfectly  developed,  and  fused  together.  Some  slight  sepa- 
ration at  their  extremities,  and  the  longitudinal  depressions  on 
their  sides,  mark  the  effort  to  form  three  roots  for  the  tooth  of 
the  upper  jaw,  and  two  for  the  lower,  according  to  the  general 

40* 


474  ORGANS  OF  DIGESTION. 

rule.  Owing  to  this  tooth  growing  at  the  posterior  extremity 
of  the  alveolar  processes,  in  a  place  where,  from  the  preceding 
development  of  the  other  teeth,  it  is  much  cramped  for  room, 
it  is  not  only  imperfectly  evolved  in  most  cases,  but  it  often 
takes  a  very  irregular  direction;  its  grinding  surface  sometimes 
looking  forwards  and  sometimes  backwards. 

The  Alveolar  Processes  in  each  jaw  form  a  semi-elliptical 
row  of  sockets,  for  the  insertion  of  the  roots  of  the  teeth  into 
them.  These  processes  and  the  teeth,  as  Mr.  Hunter  has  very 
properly  explained,  have  such  a  mutual  dependence  upon  each 
other,  that  the  destruction  of  the  one  is  inevitably  followed  by 
that  of  the  other:  "If  we  had  no  teeth,  it  is  likely  we  should 
not  only  have  no  sockets,  but  not  even  these  processes  in  which 
the  sockets  are  formed."*  The  semi-elliptical  arrangement  ob- 
served by  the  teeth  is  such,  that  when  the  mouth  is  closed,  the 
exterior  circumference  of  the  row  above  projects  beyond  those 
below;  this  is  more  obviously ihe  case  in  front;  but  it  also  pre- 
vails at  the  sides,  and  depends  primarily  upon  the  greater 
breadth  of  the  incisors  of  the  upper  jaw.  The  grinding  sur- 
face of  the  under  row,  as  a  whole,  is  slightly  concave  from  be- 
fore backwards,  while  the  opposed  surface  of  the  upper  row 
has  a  corresponding  convexity.  Each  row,  viewed  collective- 
ly, forms  a  single  edge,  in  front;  but  after  having  passed  the 
cuspidati,  it  becomes  thicker,  forms  a  double  edge,  and  is  con- 
tinued backwards  in  that  state. 


SECT  II. OF  THE  TEXTURE  AND  ORGANIZATION  OF  THE  TEETH. 

The  teeth  consist  in  two  kinds  of  substance,  one  of  which  is 
ivory  or  bone-like,  and  the  other  enamel. 

.  The  Enamel  forms  the  periphery  of  the  body  of  a  tooth,  and 
is  distinguished  by  its  whiteness,  its  brittleness,  its  semi-trans- 
parency, and  a  hardness  so  considerable  that  it  soon  takes  down 
the  edge  of  the  best  tempered  saw  or  file,  so  that  it  is  very  dif- 

*  Loc.  cit.  p.  7. 


TEXTURE  AND  ORGANIZATION  OF  THE  TEETH.         475 


ficult  to  penetrate  it.  It  forms  a  crust  upon  the  body  scarcely 
half  a  line  in  thickness,  is  more  abundant  upon  the  grinding 
surface,  and  is  reduced  to  a  thin  edge  where  it  terminates  at  the 
neck.  When  broken,  it  is  seen  to  be  fibrous,  and  the  fibres  are 
so  placed  as  to  pass  in  a  direction  from  the  surface  towards  the 
centre"  of  the  tooth :  by  which  all  the  friction  to  which  the  fibres 
are  exposed  is  applied  against  their  extremities :  an  arrange- 
ment on  the  principle  of  the  articular  cartilages,  and,  like  them, 
precisely  suited  to  resist  their  being  rubbed  down  in  mastica- 
tion, and  also  to  prevent  their  splitting. 

Enamel  consists  principally  in  a  phosphate  of  lime,  with  a 
very  small  proportion  of  gelatine.  When  immersed  in  a  weak 
acid,  its  form  is  retained,  but  the  slightest  disturbance  afterwards 
causes  it  to  crumble  down  into  a  white  pulp.  When  animals 
are  fed  upon  madder,  the  colour  of  the  enamel  is  not  affected;* 
though  it  .may  be  changed  by  dyes  applied  externally,  as  ex- 
hibited by  the  inhabitants  of  the  Pebw  Islands,  who,  by  the 
use  of  plants  turn  it  black,  and  by  persons  who  chew  tobacco, 
in  whom  it  becomes  yellow.  It  is  entirely  devoid  of  blood  ves- 
sels. When  exposed  to  heat  it  becomes  very  brittle,  cracks 
off  from  the  enclosed  bony  part  of  the  body,  and  presents  a 
singed  appearance,  from  the  small  quantity  of  gelatine  in  it. 

The  enamel  is  not  so  thick  on  the  deciduous  as  on  the  per- 
manent teeth;  it  is  thicker  on  the  cuspidati  than  on  the  incisors, 
and  on  the  first  molar  than  on  the  second  and  third.  It  is  very 
readily  dissolved  in  strong  nitric  or  muriatic  acid. 

The  Osseous  portion  of  the  tooth  is  by  much  the  most  abun- 
dant, as  it  forms  the  root,  the  neck,  and  the  body  also,  with  the 
exception  of  the  crust  of  enamel  upon  it.  In  its  texture  it 
strongly  resembles  the  petrous  bone,  and  is  even  harder  than 
it,  but  has  no  cellular  arrangement  within.  It  consists  in  a  se- 
ries of  longitudinal  laminae,  one  within  the  other,  and  when  de- 
composed presents  about  seventy  parts  of  the  phosphate  of  lime 
and  other  calcareous  combinations,  with  about  twenty  of  gela- 
tine and  ten  of  water,  f 

*  J.  Hunter,  loc.  cit.     I  have  also  verified  the  same  opinion  by  the  same  expe- 
riment, 
f  Pepys. 


476  ORGANS  OF  DIGESTION. 

The  bony  part  of  a  tooth  has  very  nearly  the  same  form  with 
the  entire  body;  hence,  upon  the  grinding  surface,  we  have  the 
same  modifications  of  shape  as  when  the  enamel  is  left  on.  The 
application  of  a  heated  iron  to  it,  turns  it  to  a  deep  black  from 
the  abundance  of  animal  matter  in  it,  which  is  one  way  to  mark 
out  decidedly  the  distinction  betwen  it  and  enamel.  The  ani- 
mal substance,  when  separated  from  the  calcareous  by  muriatic 
acid,  is  more  compact  than  the  corresponding  substance  of  bone, 
but,  like  it,  is  soft  and  flexible. 

The  bony  part  is  not  vascular;  Mr.  Hunter,  after  repeated 
trials  in  old  and  young  subjects  upon  this  point,  never  succeed- 
ed in  making  an  injection  of  it;  neither  could  he  trace  vessels 
from  the  pulp  to  a  growing  tooth.  In  growing  animals,  fed 
upon  madder,  he  found  that  the  portion  which  was  formed  pre- 
viously to  the  commencement  of  this  diet,  retained  its  primitive 
colour,  while  the  part  formed  during  the  administration  of  the 
diet  was  affected  by  it  and  turned  red:  again,  if  the  animal  were 
permitted  to  live  some  weeks  after  the  madder  was  suspended, 
to  the  preceding  condition  was  superadded  a  new  layer  of  white. 
In  this  experiment,  a  conclusive  difference  from  common  bone 
is  established;  for  besides,  in  all  cases,  the  facility  of  injecting 
the  latter  with  size,  it  is  susceptible  of  being  dyed  throughout 
by  the  administration  of  madder;  though  the  formed  parts  do 
not  take  the  latter  so  readily  as  the  forming.  These  experi- 
ments, which  are  confirmed  by  my  own  observations,  prove  sa- 
tisfactory the  total  absence  of  blood  vessels  in  the  texture  of 
the  teeth;  and  that  the  colouring  matter,  when  fixed  in  them, 
does  not  depend  upon  a  circulation,  but  upon  its  being  deposited 
as  the  tooth  grows,  and  left  there  permanently.  The  teeth  are 
consequently  not  subjected  to  a  mutation  of  particles,  and  to 
being  continually  remodelled  as  the  bones  are;  but  when  once 
formed,  they  remain  in  the  same  state,  without  change. 

Every  tooth  has  within  its  body  a  cavity,  which  varies  in 
form  and  size  according  to  the  class  to  which  the  tooth  belongs: 
this  cavity  is  continued  as  a  conoidal  canal,  through  the  whole 
length  of  each  root,  and  terminates,  by  a  small  opening,  at  its 
point.  The  cavity  is  smooth  on  its  internal  surface,  and  is 
filled  with  a  soft  pulpy  matter  which  has  no  adhesion  to  the 


TEXTURE  AND  ORGANIZATION  OF  THE  TEETH.          477 

sides  of  the  tooth,  but  receives,  through  the  opening  in  the  root, 
an  artery,  a  vein,  and  a  nerve.  The  surface  of  the  pulp  is 
moistened  by  a  slight  exhalation,  and  its  principal  bulk  seems 
to  be  formed  by  the  nerve,  on  which  the  vessels  ramify;  the 
latter  in  youth  are  much  more  abundant  than  in  old  age.*  The 
base  of  each  projection  on  the  grinding  surface  of  a  tooth  is  hol- 
lowed out  for  receiving  a  process  from  the  pulp.  The  latter  is 
supposed,  by  M.  Serres,  to  be  a  ganglion;  it  must,  however, 
be  a  point  of  much  difficulty  to  fix  this  character  upon  it,  as  the 
fine  cellular  substance  which  holds  its  constituents  together  may 
be  readily  mistaken  for  soft  nervous  fibres. 

The  arteries  of  the  teeth  of  the  upper  jaw  are  derived  from 
the  alveolar  and  the  infra-orbitar,  and  the  nerves  from  the  se- 
cond branch  of  the  fifth  pair.  The  arteries  of  the  teeth  of  the 
tower  jaw  come  from  a  single  branch  of  the  internal  maxillary, 
and  the  nerves  from  the  third  branch  of  the  fifth  pair.  The  in- 
ferior maxillary,  or  dental  artery,  and  nerve,  go  through  the 
canal  in  the  centre  of  the  spongy  structure  of  the  lower  jaw, 
and  send  off  branches  successively  to  the  roots  of  the  teeth. 
The  residue  of  the  artery  and  nerve  issues  through  the  ante- 
rior mental  foramen. 

The  teeth  have  been,  till  lately,  very  generally  ranged  among 
the  bones  belonging  to  the  skeleton ;  the  continental  anatomistsf 
are,  however,  now  more  disposed  to  view  them  as  the  produc- 
tion of  the  dermoid  tissue,  like  the  nails  and  the  hair;  and  to 
withdraw  them  from  the  class  of  bones  for  the  following  rea- 
sons. The  rudiments  of  the  bones  are  always  in  a  cartilagi- 
nous state,  and  they  are  gradually  changed  from  that  condition 
to^the  perfect  bone;  the  teeth  are  never  so,  for  the  secretion 
which  forms  them  is  from  the  beginning  deposited  in  the  state 
in  which  it  ever  afterwards  remains.  The  bones  are  all  fur- 
nished with  a  periosteum;  the  teeth  are  not,  but  have  the  sur- 
faces of  their  bodies  exposed  to  the  air.  The  general  soften- 
ing of  the  skeleton  which  occurs  in  some  cases  of  rickets,  never 
is  manifested  in  the  teeth.J  The  texture  of  the  bones  is  pene- 
trated in  every  direction  with  blood  vessels,  but  only  the  cen- 

*  Serres,  Essai  sur  1'Anat.  et  Physiol.  des  Dents,  Paris,  1817. 
t  J.  F.  Meckel,  Hipp.  Cloquet,  Breschet,  Serres,  &c. 

t  There  is,  however,  a  species  of  brittleness  of  the  teeth,  in  which  their  strength 
becomes  about  that  of  pipe  clay. 


478  ORGANS  OF  DIGESTION. 

Iral  pulp  of  the  teeth  is  furnished  with  the  latter.  The  teeth 
are  composed  of  two  kinds  of  calcarious  matter,  one  ivory-like, 
the  other  enamel;  the  bones,  on  the  contrary,  have  but  one.* 
To  this  we  may  add,  that  the  teeth  have  no  power  of  intersti- 
tial growth  like  the  bones.  It  is  also  said  by  naturalists,  that 
in  mammiferous  animals,  the  teeth  present  insensible  transitions 
from  their  most  perfect  state  to  a  lamellated  condition  resem- 
bling horns  and  nails.t  Some  animals,  as  the  shark,  have  the 
teeth  only  adhering  to  the  gum  and  not  fixed  in  sockets,  others 
have  them  in  the  stomach :  both  of  which  circumstances  serve 
to  illustrate  still  farther  the  independence  of  the  teeth  upon  the 
osseous  system;  and  that  their  being  fixed  in  sockets  belonging 
to  the  latter,  is  merely  a  collateral  and  not  an  essential  ar- 
rangement. 


SECTION  III. 

The  Gums  (Gingivce)  are  a  continuation  of  the  lining  mem- 
brane of  the  mouth  over  the  alveolar  processes,  but  its  texture 
there  is  much  changed;  as  it  becomes  more  fibrous  and  vascu- 
lar, and  loses  much  of  its  sensibility  and  capability  of  being  ex- 
tended. As  the  gums  cover  both  the  lingual  and  the  buccal  cir- 
cumference of  the  alveolar  processes,  they  adhere  very  closely 
to  the  .periosteum,  and  send  in  partitions  through  the  interstices 
between  the  teeth.  They  also  adhere  tightly  to  the  neck  of 
each  tooth,  so  that  when  the  latter  is  drawn,  the  gum,  unless 
previously  detached,  is  apt  to  be  lacerated;  this  adhesion  is  by 
a  sort  of  rounded  or  partially  doubled  edge,  that  admits  of  a 
slight  degree  of  motion,  and  which,  from  its  thickness,  if  it  be 
removed  by  ulceration  or  by  pressure,  causes  the  tooth  to  ap- 
pear to  project  unnaturally  from  its  socket.  The  teeth,  from 
being  united  to  the  jaw  by  the  gum,  and  by  the  periosteum 
being  continued  over  the  cavity  of  the  socket;  have  preserved 
to  them  that  degree  of  yielding  motion  which  prevents  them, 
on  their  unexpected  and  forcible  application  to  hard  bodies, 
from  being  fractured,  and  also  saves  their  sockets.J 

*  Serres,  loc.  cit. 

t  Traducteurs  de  J.  F.  Meckel. 

$  J.  Hunter,  loc.  cit. 


FORMATION  OF  THE  TEETH.  479 


SECT.  IV. OF  THE  FORMATION  OF  THE  TEETH. 

The  teeth,  before  they  become  visible,  are  formed  in  the  in- 
terior of  the  maxillary  bones.  Their  rudiments  consist  in  a 
vascular  pulpy  substance,  having  somewhat  the  shape  of  the 
future  tooth,  and  surrounded  by  two  membranes  or  sacs. 

The  external  sac  is  soft,  fibrous,  and  spongy,  and,  according 
to  Mr.  Hunter,  is  destitute  of  vessels.  It  lines  the  interior  of 
the  socket,  thereby  forming  its  periosteum;*  adheres  closely  by 
its  deepest  end  to  the  dental  nerves  and  blood  vessels,  and  by 
its  superficial  one  to  the  cartilaginous  thickening  which  exists 
on  the  margins  of  the  gums  of  infants.  Fox,  Blake,  and  Meckel, 
consider  this  sac  vascular,  which  I  think  more  probable,  from 
its  being  a  continuation  of  the  periosteum,  or  acting  as  such. 
Mr.  Hunter  might,  therefore,  mean  that  it  was  comparatively 
destitute  of  vessels,  and  not  totally.  It  is  more  spongy,  loose, 
and  soft,  than  the  internal  sac,  and  owing  to  its  adhesion  to  the 
gum  may,  by  pulling  at  the  latter,  be  readily  drawn  out  entire 
with  all  its  contents.  The  internal  sac  is  extremely  vascular, 
and  when  successfully  injected  appears  red  all  over;  it  is  very 
thin  and  transparent,  and  was  considered  by  Bichat  as  a  serous 
membrane.  It  adheres  to  the  external  sac  where  the  latter 
corresponds  with  the  gum;  but  is  elsewhere  detached  from  it 
with  the  exception  of  its  base,  where  it  is  united  by  the  medium 
of  the  vessels  that  penetrate  to  the  pulp,  and  in  doing  so  it  ob- 
tains its  extreme  vascularity  from  these  vessels.  Between  it 
and  the  pulp  there  is  a  mucilaginous  fluid  like  the  synovia  of 
the  joints;!  which  causes  the  internal  sac  to  protrude  like  a 
hernia,  if  a  small  puncture  be  made  through  the  parietes  of  the 
external  one.  The  internal  sac  forms  an  envelope  to  the  ves- 
sels and  nerves  of  the  pulp,  and  being  reflected  along  them, 
terminates  by  adhering  to  the  base  of  the  pulp.  When  the 
tooth  protrudes  through  the  gum,  the"  capsule  thus  formed  by 
the  two  sacs  is  perforated  at  its  apex;  and  wastes  away,  like 
the  gum,  till  the  body  of  the  tooth  is  sufficiently  advanced. 
The  two  capsules  which  are  then  to  be  considered  as  the  peri- 
osteum of  the  socket  and  of  the  root  of  the  tooth,  adhere  close- 

*  Serres,  loc.  cit.  t  Hunter,  loc.  cit. 


480  ORGANS  OF  DIGESTION. 

ly  to  the  neck  of  the  latter  and  to  its  root.  These  sacs,  or  fol- 
licles, as  they  are  sometimes  called,  are  visible  in  the  tenth 
week  of  uterine  existence. 

The  Pulp,  or  germ  of  the  tooth  (Pulpas  Dentis)  is  a  very 
vascular  body,  and  adheres  to  the  socket  only  at  its  bottom, 
where  the  vessels  enter;  it  becomes  sufficiently  distinct  about 
the  fourth  month  of  foetal  existence,  and  rises  up  then  from  the 
base  of  the  internal  membrane  of  the  sac  like  a  small  simple 
tubercle.  In  developing  itself  it  acquires  the  precise  form  pe- 
culiar to  each  tooth,  and  is  actually  the  mould  for  it:  it  is  sur- 
rounded by  a  very  fine  vascular  web,  which  is  detached  from 
it  with  much  difficulty. 

The  ossification  of  a  tooth  first  commences  on  that  surface 
of  the  pulp  next  to  the  gum,  by  one  or  more  points  according 
to  the  number  of  projections,  which  the  future  tooth  is  to  have 
on  its  grinding  surface.  The  osseous  deposite  in  its  very  early 
stage  is  thin,  soft,  and  elastic,  but  soon  acquires  a  hard  con- 
sistence. The  incisors  begin  to  ossify  by  three  points,  the  cus- 
pidatus  by  one,  the  bicuspis  by  two,  and  the  molaris  by  three, 
four  or  five.  The  several  points  of  ossification  continue  to  in- 
crease till  their  bases  come  into  contact;  they  then  coalesce, 
and  afterwards  the  tooth  grows  as  an  entire  body.  The  tritu- 
rating surface  of  the  tooth  being  first  formed  after  this  manner, 
a  deposite  of  bone  then  takes  place  along  its  edges,  till  the 
body  of  the  tooth,  with  the  cavity  in  the  centre,  is  completely 
built  up.  Jn  this  progress,  it  gradually  surrounds  the  pulp,  till 
the  whole  of  the  latter,  excepting  its  base,  is  covered  with 
bone. 

The  adhesion  of  the  pulp  to  the  new-formed  bone  is  such  as 
to  require  some  slight  force  to  separate  them;  but  this  may  be 
done  without  rupturing  either  the  one  or  the  other;  their  sur- 
faces which  were  in  contact  are  perfectly  smooth,  neither  is 
there  any  evidence  of  a  vascular  communication  between 
them.*  The  line  of  the  strongest  adhesion  is  along  the  latest 

*  Hunter,  Scrrcs,  Mcckel,  loc.  cit. 


FORMATION  OF  THE  TEETH.  481 

formed  edge  of  the  tooth,  and  that  results  from  the  exact  appo- 
sition of  the  pulp  and  it. 

The  crown  or  body  of  the  tooth  being  finally  finished,  its 
base  is  somewhat  contracted,  and  thus  forms  the  neck  of  the 
tooth.  In  the  subsequent  process  of  the  ossification  of  the  roots, 
the  number  of  the  latter  is  predetermined  and  always  indicated 
by  the  number  of  distinct  vessels  and  nerves  which  go  to  the 
pulp;  there  are,  therefore,  three  roots  to  the  upper  molares,  two 
to  the  lower,  one  to  the  incisors,  and  so  on.  When  the  root  is 
fully  formed,  its  extremity  is  tapered  off  to  a  conoidal  point ; 
and  the  canal  or  hollow  in  it  containing  the  pulp  is  diminished 
to  a  proportionate  size,  so  that  being  also  conoidal,  its  external 
end  appears  as  a  very  small  opening  not  large  enough  to  admit 
a  bristle. 

From  the  preceding  account,  it  is  clear  that  the  bony  part  of 
the  tooth  is  formed  by  an  exudation  from  the  external  surface 
of  the  pulp;  consequently,  that  the  external  lamina  of  the  crown 
is  the  first  one  deposited,  and  is  originally  of  the  size  which  it 
ever  afterwards  retains;  and  that  the  pulp  continues  this  secre- 
tion of  bony  matter,  from  the  circumference  to  the  centre;  until 
the  tooth,  (body,  neck,  and  root,)  is  completely  formed.  The 
pulp,  during  this  process,  diminishes  continually  in  size,  but 
elongates  itself  at  the  same  time  towards  the  bottom  of  the  sock- 
et; or,  in  the  words  of  Mr.  Hunter,  "  is  lengthened  into  a  fang." 

As  the  fang  grows  in  length,  the  resistance  being  at  its  end, 
causes  the  tooth  to  rise  through  the  gum;. the  socket,  in  the 
mean  time,  has  grasped  the  neck,  or  beginning  fang,  and,  being 
modelled  upon  the  root,  arises  with  it.*  Mr.  Hunter's  experi- 
ments on  animals,  interruptedly  fed  on  madder,  prove,  conclu- 
sively, that  the  bony  part  of  a  tooth  is  formed  of  lamellae,  one 
placed  within  another ;  that  the  outer  lamella  being  first  formed, 
is  consequently,  the  shortest,  and  that  the  internal  ones  lengthen 
successively. 

*  The  present  doctrine  about  the  dermoid  origin  of  tlie  teeth,  seems  to  have  pre- 
sented itself  forcibly  to  the  original  and  sagacious  mind  of  Mr.  Hunter ;  for  he 
says,  "JBoth  in  the  body  and  in  the  fang  of  a  growing  tooth,  the  extreme  edge  of 
the  ossification  is  so  thin,  transparent,  and  flexible,  that  it  would  appear  to  be 
horny  rather  than  bony,  very  much  like  the  mouth  or  edge  of  the  shell  of  a  snail 
when  it  is  growing:  and,  indeed,  it  would  seem  to  grow  mueh  in  the  same  man- 
ner,  and  the  ossified  part  of  a  tooth  would  seem  to  have  much  the  same  connexion 
with  the  pulp  as  a  snail  has  with  its  shell/'— Nat.  Hist,  of  Human  Teeth,  p.  90, 

VOL.  I. -41 


482  ORGANS  OF  DIGESTION. 

In  the  formation  of  a  molar  tooth,  when  the  body  is  finished, 
ossifications  shoot  from  its  brim,  and  proceed  to  the  centre, 
where,  by  their  union,  they  form  the  commencement  of  two, 
three,  or  even  more  roots.  Mr.  Hunter  says,  that  also  a  dis- 
tinct ossification  is  frequently  found  upon  the  centre  of  the  base 
of  the  pulp;  and  two  or  more  processes  according  to  the  num- 
ber of  roots  to  be  formed,  proceed  to  join  it  from  the  circum- 
ference of  the  tooth  ;  and  in  this  way  the  fangs  of  the  multiform 
teeth  begin. 

The  secretion  of  enamel  begins  shortly  after  the  external  la- 
minae of  the  bony  matter  commence  being  deposited.  This 
secretion,  which  has  its  mould  always  previously  formed  of  the 
bony  part,  comes  from  a  pulpy  substance  adhering  to  the  inter- 
nal face  of  the  internal  capsule.  The  pulpy  substance  is  placed 
on  the  part  of  the  capsule  nearest  to  the  gum,  and  faces  the 
pulp  which  secretes  the  bone;  whatever  eminences  the  one 
pulp  has,  the  other  has  the  same,  but  reversed,  so  that  they 
exactly  fit  upon  each  other.  This  pulp  is  best  seen  in  the  foetus 
of  seven  or  eight  months,  and  is  not  very  vascular;  it  is  much 
thinner  than  the  other,  and  decreases  in  size  as  the  development 
of  the  teeth  advances.  That  which  belongs  to  the  incisor  teeth 
is  in  contact  with  their  concave  interior  surface,  but  in  the  mo- 
lar it  is  opposed  to  their  biting  surface.* 

"  In  the  graminivorous  animals,  such  as  the  horse,  cow,  &c., 
whose  teeth  have  the  enamel  intermixed  with  the  bony  part, 
and  whose  teeth,  when  forming,  have  as  many  interstices  as 
there  are  continuations  of  the  enamel,  we  find  processes  from 
the  pulp  passing  down  into  those  interstices  as  far  as  the  pulp 
which  the  tooth  is  formed  from,  and  there  coming  into  contact 
with  it. 

"  The  enamel  appears  to  be  secreted  from  the  pulp  above 
described,  and  perhaps  from  the  capsula  which  encloses  the 
body  of  the  tooth.  That  it  is  from  the  pulp  and  capsula,,seems 
evident  in  the  horse,  ass,  ox,  sheep,  &c.;  therefore  we  have 
little  reason  to  doubt  of  it  in  the  human  species.  It  is  a  cal- 
careous earth,  probably  dissolved  in  the  juices  of  our  body,  and 
thrown  out  from  these  parts,  which  act  here  as  a  gland.  After 
it  is  secreted,  the  earth  is  attracted  by  the  bony  part  of  the  tooth, 
which  is  already  formed  ;  and  upon  that  surface  it  crystallizes, 

*  Hunter. 


FORMATION  OF  THE  TEETH.  483 

"  The  operation  is  similar  to  the  formation  of  the  shell  of  the 
egg,  the  stone  in  the  kidneys  and  bladder,  and  the  gall  stone. 
This  accounts  for  the  striated  crystallized  appearance  which 
the  enamel  has  when  broken,  and  also  for  the  direction  of  these 
strire. 

"  The  enamel  is  thicker  at  the.  points  and  bases  than  at  the 
neck  of  the  teeth,  which  may  be  easily  accounted  for  from  its 
manner  of  formation;  for  if  we  suppose  it  to  be  always  secreting 
and  laid  equally  over  the  whole  surface,  as  the  tooth  grows,  the 
first  formed  will  be  the  thickest;  and  the  neck  of  the  tooth, 
which  is  the  last  formed  part  enclosed  in  this  capsula,  must 
have  the  thinnest  coat;  and  the  fang  where  the  periosteum 
adheres,  and  leaves  no  vacant  space,  will  have  none  of  the 
enamel. 

"  At  its  first  formation  it  is  not  very  hard,  for,  by  exposing 
a  very  young  tooth  to  the  air,  the  enamel  cracks  and  looks 
rough;  but 'by  the  time  that  the  teeth  cut  the  gum,  the  enamel 
seems  to  be  as  hard  as  ever  it  is  afterwards  ;  so  that  the  air  seems 
to  have  no  effect  in  hardening  it." 

The  preceding  passages  have  been  extracted  literally  from 
Mr.  J.  Hunter's  Natural  History  of  the  Human  Teeth,  not  only 
on  account  of  their  graphical  value,  but  to  fix  upon  him  the 
merit  of  having  first  considered  the  human  teeth  as  a  secretion  ; 
an  opinion  the  originality  of  which  is  falsely  attributed  to  the 
Baron  Cuvier,  by  M.  Serres.* 

In  infants,  for  several  months  after  birth,  the  biting  margins 
of  the  gums  upon  each  jaw  are  faced  by  a  cartilaginous  rising 
of  some  lines  in  elevation,,  and  divided  by  slight  fissures.  Its 
usual  appellation  is  that  of  Dental  Cartilage  (Cartilago-Den- 
talisi)  it  performs  the  function  of  teeth,  in  retaining  the  nipple, 
and  in  mastication,  and  is  analogous  to  the  horny  beak  of  birds, 
and  of  some  reptiles;  it  only  disappears  upon  the  protrusion  of 
the  teeth.  In  the  upper  jaw  it  is  about  three  lines  wide,  and 
in  the  lower  about  two.  If  it  be  removed  by  thin  slices,  suc- 
cessively made,  till  the  margins  of  the  alveoli  appear,  one 
arrives  by  that  means  at  the  ends  of  the  dental  follicles  or 
sacs;  from  which  it  appears  that  there  is  no  intermediate  sub- 
stance. 

*  Anat.  et  Phys.  des  Dents,  p.  63, 


484  ORGANS  OF  DIGESTION. 

In  the  preceding  cartilage  are  found  many  small  glands, 
grouped  about  in  different  parts  of  it.  They  were  discovered 
within  a  few  years  past  by  M.  Serres,*  of  Paris;  are  about  the 
size  of  a  millet  seed,  contain  a  whitish  fluid,  and  when  examined 
by  the  aid  of  a  microscope  do  not  appear  to  have  any  distinct 
opening  or  duct,  in  consequence  of  which  they  must  be  punctured 
in  order  to  expel  their  contents.  The  largest  of  them  are  on  the 
internal  side  of  the  gum  near  the  molar  teeth. 

According  to  their  discoverer,  these  glands  serve  to  lubricate 
the  dental  cartilages  of  the  infant,  but  after  the  protrusion  of  the 
teeth  they  secrete  the  substance  commonly  called  Tartar,  and 
heretofore  falsely  attributed  to  the  saliva.  Their  secretion  being 
of  a  fatty  nature,  keeps  up  the  high  and  brilliant  polish  which  the 
teeth  have  till  middle  age;  it  being  afterwards  altered,  the  teeth 
then  become  more  dull  and  yellow.  Salivation  produces  an  ex- 
cessive secretion  and  deposite  of  tartar  from  these  glands.  J.  F. 
Meckel  states,  that  he  has  never  been  able  to  discover  them  till 
towards  the  period  of  dentition,  from  which  he  is  rather  induced 
to  consider  them  as  a  morbid  production  depending  upon  irri- 
tation, and  probably  not  differing  from  little  abscesses. 


SECT.  V. —  DENTITION. 

Infants  have  a  set  of  teeth  called  Deciduous,  from  their  being 
lost  after  a  certain  period  of  time.  Their  whole  number  is  twen- 
ty, ten  in  each  jaw,  consisting  on  either  side  of  two  incisors;  one 
cuspidatus;  and  two  molares,  having  a  shape  corresponding  with 
that  of  the  large  grinders  in  the  adult.  Several  of  these  teeth 
fall  out  about  the  seventh  year,  and  all  of  them  have  disappeared 
about  the  fourteenth.  The  time  of  their  first  protrusion  through 
the  gums  is  variable,  but  may,  as  a  general  rule,  be  stated  at 
from  the  sixth  to  the  eighth  month  after  birth.  They  appear 
commonly  in  pairs.  The  pairs  of  the  lower  jaw  have  prece- 
dence in  their  protrusion;  and  are  immediately  followed,  suc- 
cessively, by  their  congeners  in  the  upper.  The  order  of  pro- 
trusion is  as  follows : — 

The  two  central  incisors,  from  the  sixth  to  the  eighth  month ; 

The  two  lateral  incisors,  from  the  seventh  to  the  tenth  month ; 

*  Loc.  cit. 


DENTITION.  485 

The  first  molar  tooth,  on  each  side,  from  the  twelfth  to  the 
fourteenth  month ; 

The  cuspated,  from  the  fifteenth  to  the  twentieth  month; 

The  second  molar,  on  each  side,  from  the  twentieth  to  the 
thirtieth  month.* 

The  Deciduous  teeth,  by  a  process  which  will  be  presently  ex  - 
plained,  drop  from  the  gums  and  are  succeeded  by  the  perma- 
nent teeth.  The  first  permanent  molar,  about  six  or  seven  years 
of  age,  by  emerging  behind  the  second  infant  molar,  leads  the 
way  to  the  second  epoch  of  dentition  which  occurs  in  the  fol- 
lowing order: — 

The  central  infant  incisors  fall  out  about  the  sixth  or  seventh 
year,  and  are  immediately  followed  by  the  central  perma- 
nent incisors ; 

In  a  few  months  afterwards,  sometimes  at  the  same  period, 
the  lateral  infant  incisors  tumble  out,  and  are  succeeded  by  the 
lateral  permanent  incisors; 

About  the  ninth  year  the  first  molar  teeth  fall  out,  and  are 
succeeded  by  the  first  bicuspated ; 

From  the  ninth  to  the  eleventh  year,  the  second  molars  fall 
out,  to  be  succeeded  by  the  second  bicuspated; 

From  the  eleventh  to  the  twelfth,  the  infant  cuspated  are  fol- 
lowed by  the  adult  cuspated  ; 

About  the  end  of  the  twelfth  year,  the  second  permanent 
molars  protrude  behind  the  first  permanent; 

And,  finally,  from  the  sixteenth  to  the  twenty-fifth  year,  the 
third  permanent  molars  or  the  Dentes  Sapientias,  make  their 
appearance. . 

In  the  jaw  of  a  fcetus  of  three  or  four  months  after  conception, 
the  beginning  of  the  alveolar  processes  may  be  observed,  in  the 
condition  of  a  longitudinal  groove,  deeper  and  more  narrow  in, 
front,  more  shallow  and  wider  behind;  and  in  the  bottom  of  the. 
groove  are  small  transverse  ridges,  dividing  it  into  superficial 
depressions.  From  this  simple  condition,  ridges  begin  to  shoot 
out  from  the  opposite  sides  of  the  canal  near  its  brim  ;  and  form, 
by  their  junction,  arches  across  it;  more  matter  being  added  to 
these  arches,  they  make,  in  their  progress,  a  sort  of  cell  for  each 

*  Serres,  loc.  cit. 

41* 


486  ORGANS  OF  DIGESTION. 

tooth,  open  on  its  alveolar  surface.  This  opening  is  nearer  the 
internal  circumference  of  the  alveolar  processes,  so  that  the  teeth 
are  almost  covered,  and  probably  for  the  reason  advanced  by 
Mr.  Hunter,  that  the  gums  may  be  firmly  supported  before  the 
teeth  come  through. 

The  rudiments  of  the  teeth  which  are  earliest  in  their  appear- 
ance may  be  found  in  a  fetus  of  two  or  two  and  a  half  months; 
and  at  the  expiration  of  three  months,  it  is  said  that  all  the  germs 
of  both  sets  of  teeth  exist  in  a  manner  to  be  distinguished.*  The 
germs  of  this  period  are  lodged  in.  membranous  folds  belonging 
to  the  gum,  to  which  the  germs  of  the  first  dentition  are  imme- 
diately attached,  while  those  of  the  second  are  suspended  by 
pedicles  of  a  line  or  two  in  length,  which  circumstance  alone 
permits  them  to  be  distinguished.  At  four  months  all  the  germs 
are  contiguous  to  each  other,  with  the  exception  of  the  incisors; 
shortly  afterwards  they  begin  to  be  separated  by  the  rudiments 
of  the  alveolar  processes  ;  and  about  the  fifth  month  ossification 
is  perceptible  in  the  infant  incisors,  and  goes  on  in  the  other  teeth 
very  much  in  the  order  of  their  appearance. 

The  germs  of  the  deciduous  teeth  are  placed  in  an  arc  of  a 
circle,  the  cuspidati  being  thrown  forwards  out  of  the  line  of  the 
others  and  somewhat  lower;  in  consequence  of  which,  the  first 
molar  border  closely  upon  the  incisors  The  germs  of  the  per- 
manent teeth  are  brought  into  view  by  removing  the  internal 
face  of  the  jaw,  and  are  at  the  posterior  upper  side  of  the  first 
germs  ;  being,  therefore,  nearer  to  the  edges  of  the  alveolar  pro- 
cesses. 

At  birth,  ossification  has  taken  place  in  all  the  infant  teeth, 
though  their  roots  are  not  yet  completed.  The  rudiments  of  the 
permanent  teeth,  though  seen  at  an  early  period  of  fcetal  ex- 
istence, do  not  be^in  to  ossify  till  after  birth.  Thus,  the  first 
adult  incisor  and  molar  begin  to  ossify  about  the  fifth  or  sixth 
month  of  life,  the  second  incisor  and  cuspidatus  about  the  ninth 
month,  the  first  bicuspis  about  the  fifth  year,  the  second  bicuspis 
and  second  molar  about  the  sixth  or  seventh,  and  the  third  mo- 
lar about  the  twelfth  year.t 

The  teeth  which  have  no  predecessors  are  in  consequence 
of  their  adhesion  to  the  gum  brought  out  in  their  regular  places; 
*  Serres,  p.  3.  t  Hunter. 


DENTITION.  487 

but,  in  the  case  of  such  permanent  teeth  as  take  the  position  oc- 
cupied by  the  deciduous,  there  is,  before  the  teeth  protrude,  a 
pedicle,  (Gubernaculum  Dentis,)  which  passes  from  the  alveolar 
end  of  the  sac  of  the  permanent  tooth  to  the  sac  of  the  decidu- 
ous tooth;  and  even  when  the  latter  is  fully  formed  and  pro- 
truded, the  same  pedicle  may  be  traced  to  that  part  of  the  gum 
•surrounding  the  neck  of  the  deciduous  tooth.*  At  birth,  the 
rudiments  of  fifty-two  teeth  may  be  found  in  the  two  jaws; 
and,  as  a  general  rule  at  that  period,  the  rudiments  of  the  per- 
manent are  more  superficial  than  those  of  the  deciduous;  but 
their  position  is  subsequently  changed,  so  that  the  first  descend 
while  the  latter  ascend. t 

As  the  permanent  teeth  are  preparing  to  protrude,  the  alveo- 
lar cavities,  in  which  they  are  contained,  form  orifices  on  the 
internal  surface  of  the  jaw  near  the  edges  of  the  deciduous  al- 
veolar processes,  and  which  are  called  the  Alveolo-dental  Ca- 
nals, (Itinera  Dentium.)  Those  for  the  incisor  and  canine  teeth, 
are  just  behind  their  corresponding  deciduous  teeth,  and  those  for 
the  bicuspated  near  and  somewhat  behind  the  infant  molares. 
At  this  period,  a  bony  septum  separates  almost  completely  the 
two  orders  of  alveolar  cavities  from  each  other,  and  there- 
by prevents  their  mutual  interference. 

The  permanent  teeth  being  thus  formed  in  new  and  distinct 
sockets,  and  being  kept  off'  from  the  deciduous,  it  is  clear  that 
the  latter  cannot  be  pushed  out  of  their  alveoli,  as  is  sometimes 
supposed,  by  the  growth  of  the  former;  and  if  it  did  take  place, 
it  would  produce  the  great  inconvenience  of  causing  them  to  rise 
up  into  the  mouth,  beyond  the  level  of  the  other  teeth.  On  the 
contrary,  the  deciduous  teeth  are  made  loose  by  the  removal  of 
their  roots,  which  progresses  till  nothing  but  the  neck  is  left,  and 
then  the  slightest  force  applied  dislodges  them  from  their  posi- 
tion on  the  gum.  This  decay  of  the  root  is  not  even  affected, 
according  to  Mr.  Hunter,  by  the  pressure  of  the  rising  tooth,  for 
the  new  alveoli  rise  with  the  new  teeth,  and  the  old  ones  decay 
along  with  their  decaying  fangs;  and  when  the  first  set  falls 
out,  the  succeeding  teeth  are  enclosed  by  a  complete  bony  sock- 
et; from  which  it  is  evident  that  the  change  is  not  produced  by 

*  J.  Cloquet,  Anat.  PI.  XXII.  fig.  16,  17.     Serres,  loc.  cit.  p.  109. 
•f-  Serres. 


488  ORGANS  OF  DIGESTION, 

mechanical  pressure,  but  is  a  particular  process  in  the  animal 
economy.*  In  farther  proof,  however,  Mr.  Hunter  has  seen  two 
or  three  jaws  where  the  second  deciduous  grinders  were  shed- 
ding by  the  decay  of  their  roots,  without  there  being  under- 
neath any  tooth  to  press  upon  them  ;  and  in  another  jaw  he  ob- 
served the  same  circumstance  in  both  grinders.  In  a  female 
patient,  in  whom  the  last  temporary  molar  was  loose,  and  was 
pulled  out  in  consequence,  it  was  not  succeeded  by  another 
tooth.  One  of  these  patients  at  the  time  was  aged  twenty,  and 
the  other  thirty;  from  which  it  would  appear,  that  though  the 
wasting  of  the  fang  of  a  deciduous  tooth  does  not  depend  upon 
the  pressure  of  the  permanent  one,  yet  the  latter  determines, 
in  some  measure,  its  expulsion,  as,  without  some  such  influence, 
the  period  of  shedding  would  not  have  been  so  late. 

From  these  observations  of  Mr.  Hunter,  it  would  appear, 
that  the  pressure  of  the  permanent  tooth  is  not  indispensable  to 
the  removal  of  the  deciduous  one  in  all  cases ;  yet  I  think  it 
will  be  most  frequently  found  that  much  of  the  decay  of  the 
root  of  the  deciduous  tooth  is  owing  to  its  being  absorbed  by 
the  pressure  of  the  body  of  the  permanent  one.  The  alveoli 
of  the  latter,  judging  from  my  own  observations,  are  seldom 
so  perfect  towards  the  period  of  their  protrusion  as  to  form  a 
complete  separation  of  the  two  orders  of  teeth,  and  even  when 
the  alveoli  are  perfect,  they  are  made  to  press  upon  the  root  of 
the  deciduous  tooth  by  the  evolution  of  the  body  of  the  perma^ 
nent. 

Besides  the  deciduous  teeth  being  loosened,  as  stated  by  MrK 
Hunter,  by  the  absorption  of  their  alveolar  cavities  while  the 
fangs  are  dissappearing,  the  following  process  occurs.  The 
permanent  teeth  protrude  within  the  circle  of  the  deciduous, 
the  arch  of  the  latter  is  weakened,  and  its  several  pieces  are  in 
that  way  detached  by  a  force  acting  from  within  outwards; 
this  influence  being  much  assisted  by  the  obliteration  of  the  al- 
veolar cavities  proceeding  principally  at  their  outer  circumfe- 
rence. The  latter,  however,  is  not  so  obviously  the  case  with 
the  molar  as  with  the  incisive  and  canine  teeth. 

The  deciduous  teeth,  even  before  they  are  loosened  by  the 
absorption  of  their  fangs  and  of  their  alveolar  processes,  are 
much  more  easily  extracted  in  proportion  than  the  adult  teeth, 

•  Hunter,  loc. 


ATTACHMENT  OF  TEETH.  489 

from  the  texture  of  their  periosteum  being  much  softer  and 
more  yielding. 

A  question  of  some  interest  has  recently  arisen  in  regard  to 
the  precise  apparatus  of  attachment  of  the  fangs  of  both  sets  of 
teeth  to  their  alveolar  cavities.  The  principal  cause  of  attach- 
ment is  attributed  to  a  distinct  ligament  or  fasciculus  for  each 
tooth,  having  for  its  position  the  side  of  the  tooth  the  most  dis- 
tant from  the  front  line  of  the  symphysis  of  the  jaws.  The  liga- 
ment thus  situated  is  said  to  arise  from  the  edge  of  the  alveo- 
lus between  the  teeth,  and  proceeding  forwards  in  the  case  of 
the  molars,  and  inwards  in  the  case  of  the  incisors:  to  be  inserted 
into  the  neck  of  the  tooth  not  quite  the  sixteenth  part  of  an  inch 
from  the  enamel.  The  ligamentous  character  is  considered  as 
very  distinct,  the  fibres  being  white  and  shining  like  tendon. 
The  exclusive  cutting  of  it  is  also  said  to  facilitate  very  much 
the  extraction  of  a  tooth.* 

My  own  observations,  made  upon  the  parts  softened  in  mu- 
riatic acid,  and  in  the  recent  state,  have  not  led  me  to  see  the 
ligamentum  dentis  in  so  distinct  a  light  or  to  witness  the  extreme 
facility  of  extraction  after  it  alone  is  cut.  It  is,  however,  pro- 
bable that  the  insinuation  of  an  instrument  between  the  tooth 
and  alveolus  will  generally,  to  the  extent  of  the  incision,  dimi- 
nish the  force  of  resistance  in  pulling  the  tooth  out.  The  ac- 
tual adhesion  of  the  tooth  to  the  alveolus  appears  to  me  to 
arise  from  the  original  capsules  of  the  teeth  being  converted 
into  a  single  layer  of  periosteum,  one  surface  of  which  ad- 
heres to  the  alveolus,  and  the  other  to  the  fang  of  the  tooth. 
The  adhesion  I  have  found  particularly  strong  at  the  margin 
of  the  alveolus,  and  converging  circularly  from  it  to  the  neck  of 
the  tooth,  somewhat  in  the  manner  of  a  coronary  ligament. 
Another  subject  of  remark  is,  that  the  filaments  of  periosteum 
are  not  laid  down  laterally  to  the  teeth,  but  one  end  of  the  fila- 
ment adheres  to  the  alveolus,  and  the  other  to  the  tooth,  like 
the  filaments  of  the  interosseous  ligament  at  the  lower  junction 
of  the  tibia  and  tibula.  In  this  way  a  cap  of  such  fibres  is  found 
over  the  whole  fang  of  the  tooth:  one  of  the  best  means  of  de- 

*  See  Description  of  the  Ligamentum  Dentis,  by  Paul  B.  Goddard,  M.  D.  in 
Am.  Journ.  of  Med.  Sciences,  vol.  xxiii.  Phil.  1839. 


490  ORGANS  OF  DIGESTION. 

monstrating  it,  is,  to  chip  off  the  alveolus  in  front  of  a  cuspate 
to@th  of  the  lower  jaw,  then  seize  the  body  of  the  tooth  with  a 
pair  of  strong  pliers,  and  make  it  rotate  on  its  axis,  the  fibres 
will  thus  be  seen  to  start  up  and  to  show  the  attachment  of  their 
two  ends,  one  to  the  alveolus  and  the  other  to  the  tooth.  The 
jaw  of  a  strong  muscular  subject  is  especially  recommended. 
This  arrangement  of  the  course  of  the  fibres  is  very  well  exhi- 
bited in  the  cow  and  horse. 

In  the  lower  jaw  of  the  adult,  there  is  but  one  arterial  trunk, 
which  supplies  the  teeth;  but,  in  the  fo6tus,  and  till  the  age  of 
six  or  seven  years,  there  are  two  arteries,*  and  as  many  canals 
for  containing  them.  The  lowest  of  these  arteries  belongs, 
exclusively,  to  the  deciduous  teeth;  it  is  distinctly  visible  in  the 
foetus,  augments  till  the  third  or  fourth  year,  afterwards  it 
shrinks,  and  is  obliterated  about  the  sixth  or  seventh  year.  In 
some  rare  cases  its  canal  remains  open  for  a  longer  time,  as 
M.  Serres  has  met  with  it  in  a  woman  of  thirty.  Being  a  branch 
from  the  inferior  maxillary,  it  enters  the  bone  at  a  foramen 
somewhat  lower  down  than  the  posterior  maxillary;  and  what 
remains  of  it  after  the  teeth  are  supplied  comes  out  at  another 
aperture,  a  little  below  the  anterior  maxillary  foramen,  and 
there  anastomoses  with  the  other  dental  artery. 

M.  Serres  supposes  that  this  artery,  discovered  by  himself, 
and  obviously  serving  in  the  evolution  of  the  deciduous  teeth, 
by  being  obliterated  before  they  fall  out,  destroys  their  vitality, 
and,  therefore,  they  become  absolutely  foreign  bodies,  the  ex- 
pulsion of  which  is  required  by  nature  on  common  principles. 

SECT.   VI. OF  IRREGULARITIES  IN  DENTITION. 

^ 

The  process  in  certain  individuals  is  premature;  Louis  XIV 
was  born  with  two  teeth;  many  instances  of  the  same  sort  o 
precosity  are  recorded  by  Haller,  and  other  medical  writers,  in 
some  of  which  even  ten  teeth  were  found  protruded  at  birth. 

On  other  occasions,  the  process  is  retarded  in  a  manner  equal- 
ly striking,  and  varying  from  the  tenth  month  to  the  sixth  or 
seventh  year.     This  unusual  tardiness  is  sometimes  manifested 
in  particular  teeth;  thus,  I  know  a  young  gentleman  in  whom 
*  Serres,  loc.  cit.  p.  17, 


IRREGULARITIES  IN  DENTITION.  491 

one  of  the  permanent  incisors  of  the  upper  jaw  did  not  come 
down  before  the  fourteenth  year.  Borelli  reports  a  woman  in 
her  sixtieth  year  who  never  had  teeth;  a  magistrate  of  Frede- 
rickstadt  lived  to  an  advanced  age,  and  never  had  either  canine 
or  incisor  teeth;  he  was  however  furnished  with  molares. 

The  teeth  are  sometimes  supernumerary;  it  is  not  very  un- 
common to  see  this  manifested  by  a  single  canine  or  incisor, 
and  more  frequently  in  the  upper  jaw  than  in  the  lower.  Occa- 
sionally, there  are  several  supernumerary  teeth. 

Cases  are  recorded  in  which  several  teeth  have  been  fused  or 
joined  together.  Bernard  Gengha  reports,  that  in  a  pile  of  bones 
belonging  to  the  Hospital  S.  Esprit,  at  Rome,  he  found  a  cra- 
nium in  which  there  were  only  three  teeth;  in  the  two  upper 
maxillse  one  occupied  the  space  of  all  the  incisors  and  the  two 
cuspidati,  and  each  of  the  others  the  space  of  all  the  molares  of 
its  respective  side.*  According  to  the  historians  Plutarch  and 
Valerius  Maximus;  Pyrrhus,  king  of  Epirus,  and  Prusias,  king 
of  Bithynia,  had  a  single  dental  piece  in  each  jaw,  which  stood 
in  the  place  of  the  usual  allowance  of  sixteen  teeth.  These, 
cases  are  scarcely  credible,  for  the  reason,  that  for  them  to 
have  occurred,  the  middle  palate  suture,  which  is  slow  inform- 
ing, and  divides  the  germs  of  the  two  sides  from  each  other, 
could  not  have  existed  during  the  foetal  state,  at  any  time  sub- 
sequent to  the  third  month;  or  what  is  more  compatible  with 
this  account,  at,  no  time  whatever.  It  is  more  probable,  there- 
fore, that  notwithstanding  the  royal  opportunities  of  cleanliness 
possessed  by  these  persons,  their  teeth  were  neglected,  and  per- 
mitted to  incrust  themselves  with  a  dense,  thick  coat  of  tartar, 
which  gave  them  the  appearance  of  a  single  piece:  a  circum- 
stance which  occurred  to  Sabatier,  in  a  girl  of  fifteen  or  six- 
teen, and  to  Fournier  in  an  individual  of  the  same  ageandsex.t 
Another  objection  is,  that  as  the  common  law  of  the  germs  is 
to  develop  themselves,  and  to  ossify  at  different  epochs,  in  these 
two  cases  they  were  all  not  only  proceeding  at  the  same  rate,  but 
also  joining  one  another  so  as  to  form  but  a  common  sac,  con- 
founding, thereby,  all  the  known  phenomena  of  dentition. 

In  most  persons  there  are  but  two.  sets  of  teeth;  it  .has  hap- 
pened, however,  in  several  instances,  for  people  about  the  age  of 
seventy  to  have  one  or  more  new  teeth  belonging  to  a  third  set: 

*  Sabatier,  Anat.  tome  1,  p.  78.         f  Diet,  des  Sc.  Med. 


492  ORGANS  OF  DIGESTION. 

they  are  commonly  incisors.  J.  Hunter  saw  an  example  of  the 
kind.*  The  Countess  of  Desmond,  who  lived  to  her  hundred 
and  fortieth  year,  had,  at  this  period,  according  to  Bacon,  a 
third  set  of  teeth.t  Mentzelius  narrates  a  similar  casej  in  the 
following  words:  having  accompanied  the  Elector  of  Branden- 
burg on  a  visit  to  Cleves,  in  1666,  there  arrived,  at  the  same 
time,  a  man  aged  one  hundred  and  twenty,  who  exhibited  him- 
self for  money,  and  whom  I  saw  at  the  court  of  the  Elector. 
His  strength  of  voice  manifested  that  of  his  breast,  and  he  having 
run  over  the  gamut,  was  heard  at  more  than  a  hundred  paces 
off.  Having  then  opened  his  mouth,  he  showed  us  two  rows  of 
pearly  teeth,  and  on  the  subject  of  their  beauty  related  '  that  be- 
ing at  the  Hague  two  years  before,  on  the  same  errand  which 
brought  him  to  Cleves,  there  arrived  an  Englishman  aged  one 
hundred  and  twenty;  that  he  visited  the  latter,  and  addressed 
him  in  the  following  terms:  '  We  are  nearly  of  the  same  age, 
for  I  am  only  two  years  younger  than  you,  and  I  have  had  the 
greatest  desire  to  see  one  older  than  myself,  for  I  have  felt  no 
inconvenience  till  lately;  but  during  the  three  days  that  I  have 
been  here,  I  have  had  severe  headach  and  dreadful  pains  in  the 
jaws,  which  convince  me  that  I  am  about  to  die.'  '  You  are 
mistaken,  my  dear  friend,' said  he  to  me:  'on  the  contrary, 
you  are  becoming  younger,  for  you  are  about  to  teethe  again 
like  an  infant.'  «  Oh !'  answered  I,  'I  pray  to  God  not  to  punish 
me  by  prolonging  my  days.'  « I  left  him  then  and  went  to  bed, 
and  immediately  after  felt  the  most  excruciating  pains  in  the 
jaws,  which  were  followed  by  the  protrusion  of  the  teeth  that 
you  now  see."J 

The  circumstance  of  a  third  dentition,  has  given  rise  to  a  ques- 
tion among  physiologists,  whether  the  germs  are  primarily  super- 
numerary ?  or  whether  the  gums  have  within  themselves  organs 
capable  of  forming  and  of  producing  new  teeth? 

When  such  teeth  come  out  in  a  straggling  manner,  they  hurt 
the  opposite  jaw,  and  require  to  be  extracted. 

In  old  persons  who  have  lost  all  their  teeth,  there  is  a  carti- 
laginous hardening  of  the  gum,  as  in  infancy,  whereby  they  still 
retain  some  power  of  mastication. 

When  the  body  of  the  tooth  has  been  worn  away,  nature  pre- 
vents the  exposure  of  its  cavity  by  the  deposite  of  new  matter, 

*  Loc.  cit.  p.  85.  t  Hist,  vit  et  mort.  Col.  536. 

t  Serres,  loc.  cit.  p.  40. 


MUSCLES  OF  THE  TONGUE.  493 

which  may  be  known  by  its  darker  colour,  and  by  its  transpa- 
rency. 

The  muscles  of  mastication  being  the  Temporalis,  the  Mas- 
seter,  the  Pterygoideus  Intern  us,  and  the  Pterygoideus  Exter- 
nus,  their  description  may  be  seen  elsewhere. 


CHAPTER  III, 

OF  THE  TONGUE. 

THE  Tongue  (Lingua)  is  the  principal  organ  of  taste,  and  is 
also  concerned  in  mastication  and  in  speech.  It  is  an  oblong, 
flattened,  symmetrical,  muscular  body,  which  extends  from  the 
os  hyoides  posteriorly  to  the  incisor  teeth  anteriorly,  and,  being 
placed  at  the  bottom  of  the  mouth,  fills  up  the  space  within  the 
two  sides  of  the  body  of  the  lower  jaw.  The  exact  extent  of  room 
which  it  occupies,  varies  according  to  its  being  in  a  state  of  re- 
pose or. of  activity. 

The  posterior  extremity  of  the  tongue  is  called  its  base  or 
root,  and  arises  muscular  from  the  body  and  the  cornua  of  the 
os  hyoides;  it  is  there  considerably  thinner  than  elsewhere,  it  also 
has  a  fibro-muscular  origin  from  the  centre  of  the  epiglottis  car- 
tilage: sometimes  a  cartilage  is  found  in  the  middle  of  the  base, 
and  which  forms  a  sort  of  ball  and  socket  joint  with  the  os  hy- 
oides. Its  anterior  extremity  is  called  the  tip  or  point,  is  loose, 
and  has  a  rounded  thin  termination.  Between  the  point  and 
the  base  is  the  body.  The  superior  surface  of  the  tongue  is  flat, 
is  divided  by  a  middle  longitudinal  fissure  of  inconsiderable 
depth  into  two  equal  parts,  and  is  covered  by  the  lining  mem- 
brane of  the  mouth,  under  a  particular  modification  of  structure. 
The  inferior  surface  of  the  tongue,  with  the  exception  of  its 
middle  part,  is  also  free,  and  covered  by  the  common  mucous 
membrane  of  the  mouth;  but  the  latter  is  there  very  thin,  and  the 
veins  may  be  readily  seen  shining  through  it. 

SECT.  I. — MUSCLES  OF  THE  TONGUE, 

The  muscles  which  compose  the  principal  part  of  the  bulk  of 
the  tongue,  are,  the  Stylo-glossus,  the  Hyo-glossus,  the  Genio- 
VOL.  I.— 42 


494  ORGANS  OF   DIGESTION. 

hyo-glossus,  and  the  Lingualis.  As  these,  besides  belonging  to 
the  general  muscular  system,  also  form  so  important  a  part  of 
this  organ,  with  a  view  of  collecting  the  account  of  its  struc- 
ture, their  description  will  be  repeated. 

1.  The  Stylo-glossus  arises  from  the  styloid  process  of  the 
temporal  bone,  and  soon  reaches  the  side  of  the  base  of  the 
tongue.     Some  of  its  fibres   extend   to  the  tip  and  confound 
themselves  along  with  those  of  the  superficial  lingual  muscle, 
above  and  below  the  margin  of  the  tongue:  while  others  form  a 
broad  transverse  fasciculus,  which  is  united  to  the  correspond- 
ing portion  of  the  other  side  in  the  region  of  the  greater  pa- 
pillae.* 

2.  The  Hyo-glossus  arises  from  the  side  of  the  base  of  the  os 
hyoides,  from  its  cornu;  and  from  its  appendix,  in  a  slight  degree. 
It  is  placed  within  the  stylo-glossus,  and  extends  forwards  to 
the  tip  of  the  tongue.     Some  of  its  fibres  go  as  far  as,  the  mid- 
dle line  of  the  tongue;  others  rise  almost  perpendicularly  up- 
wards to  its  base;   while  the  remainder  are  confounded,  along 
the  margin  of  the  tongue,  with  the  superficial  lingual  muscle. 

3.  The  Genio-hyo-glossus  arises  from  the  tubercle  on  the 
posterior  face  of  the  symphysis  of  the  lower  jaw,  and  imme- 
diately after  its  origin  spreads  itself  after  the  manner  of  a  fan. 
Its  inferior  fibres  are  inserted  into  the  base  of  the  os  hyoides, 
while  the  remainder,  by  their  diverging,  are  inserted  into  the 
whole  length  of  the  tongue  from  its  base  to  its  point.     This 
muscle  is  in  contact,  side  by  side,  with  its  fellow,  and  there  is 
a  sort  of  fissure  with  a  small  quantity  of  adipose  matter  be- 
tween them. 

As  the  fibres  of  this  muscle  go  from  below  upwards,  they  pe- 
netrate to  the  upper  surface  of  the  tongue;  and,  consequently, 
traverse  the  transverse  lingual  muscles  and  the  superficial  lin- 
gual. 

4.  The  Lingualis  is  a  small  narrow  fasciculus  of  fibres,  which 
arises  indistinctly  about  the  root  of  the  tongue,  in  the  yellow 

*  See  Cloquet's  Anat.  pi.  CXX. 


MUCOUS  COVERING  OF  THE  TONGUE.  495 

cellular  tissue  there,  and  advances  to  the  tip  between  the  liyo- 
glossus  and  the  genio-hyo-glossus. 

5.  The  Superficial  Lingual  Muscle  (Superficialis  Linguce)  is 
a  broad,  thin  layer,  covering  the  upper  surface  of  the  tongue, 
below  the  mucous  membrane;  it  begins  behind,  on  a  line  with 
the  greater  papillas,  and  advances  forwards  to  the  tip.     Its  more 
internal  fibres  converge  and  end  at  the  middle  line,  but  the  ex- 
ternal ones  terminate  above  and  below,  near  the  margin  of  the 
tongue. 

6.  The  Transverse  Lingual  Muscles  (Transver sales  Lingua,} 
consist  in  small  scattered  fasciculi,  which  are  placed  below  the 
last,  and  in  the  thickness  of  the  tongue,  which  they  traverse  at 
right  angles.    One  end  of  them,  on  each  side,  ceases  at  the  mid- 
dle line  of  the  tongue,  where  there  is  a  small  seam,  and  the 
other  end  terminates  in  the  covering  membrane  of  the  tongue, 
at  the  lateral  margin  of  this  organ.     These  fibres  are  to   be 
found  in  the  whole  length  of  the  tongue,  and  gradually  become 
more  curved  at  its  base. 

7.  The  Vertical  Lingual  Muscles  (Verticales  Linguce)  extend 
from  the  upper  to  the  under  investing  membrane  of  the  tongue. 
They  consist  in  small  scattered  fasciculi,  like  the  preceding, 
and  cross  them  at  right  angles  in  traversing  the  thickness  of 
the  tongue.*     Many  of  these  fibres  appear  to  me  to  proceed 
from  the  genio-hyo-glossus. 

SECT.  II. MUCOUS  COVERING  OF  THE  TONGUE. 

The  mucous  membrane  of  the  mouth,  where  it  forms  the  fra3- 
num  linguas,  is  over  the  anterior  margin  of  genio-hyo-glossi 
muscles;  the  same  membrane,  in  going  from  the  base  of  the 
tongue  to  the  epiglottis,  and  forming  another  frasnum,  has,  on 
each  side  of  it,  a  depression  or  pouch  in  which  articles  of  food 
sometimes  lodge.  Beneath  the  last  fraenum  is  a  ligamentous 
tissue  which  runs  to  the  base  of  the  tongue  from  the  front  of 
the  epiglottis,  and  serves  to  keep  the  latter  erect:  some  mus- 

*  The  preceding  views  of  the  minute  muscular  structure  of  the  tongue  have 
lately  been  advanced  by  M.  Gerdy,  of  Paris.  See  J.  Cloquet,  Anat.  de  L'Homme, 
pi.  CXIX.  CXX.  J,  F.  Meckel,  loc.  cit.  Note  des  Traducteurs,  vol.  iii.  p.  313. 


496  ORGANS  OF  DIGESTION. 

cular  fibres  are  occasionally  seen  in  this  tissue  in  the  human 
subject :  in  the  black  bear  of  North  America,  and  in  some 
other  animals,  it  consists  in  a  pair  of  strong  muscles.  The 
pouch,  on  each  side,  is  bordered,  externally,  by  a  more  super- 
ficial doubling  of  the  mucous  membrane,  which  passes,  from 
the  base  of  the  tongue  to  the  side  of  the  epiglottis.* 

The  lingual  portion  of  the  lining  membrane  of  the  mouth,  on 
the  upper  surface  of  the  tongue,  is  somewhat  cartilaginous,  and 
into  it  is  inserted  many  of  the  subjacent  muscular  fibres.  At 
the  base  of  the  tongue  this  cartilaginous  condition  is  deficient, 
and  its  place  is  supplied  by  a  yellow  cellular  tissue  which  ad- 
heres to  the  os  hyoides,  to  the  epiglottis,  and  to  many  muscular 
fibres  below,  and  has  in  it  numerous  mucous  follicles. 

As  observed,  the  mucous  membrane,  on  the  under  surface  of 
the  tongue,  offers  no  peculiarity  of  organization :  but,  on  the  up- 
per surface,  it  is  remarkable  for  the  unusual  size  and  develop- 
ment of  its  papillae,  for  having  its  epidermis  easily  detached,  and 
also  for  having  the  muscular  structure  beneath  fixed  to  it  with 
extreme  closeness. 

The  anterior  two-thirds  of  the  upper  surface  of  the  tongue 
are  entirely  covered  by  these  papilla.  They  are  so  thickly 
set  as  to  touch  one  another ;  and,  as  they  present  some  pecu- 
liarities of  form,  they  are  divided  into  Papillae  Maximae  or  Ca- 
pitata?,  Media?,  Villosae,  and  Filiformes. 

The  Papillae  Maximae  constitute  the  posterior  border  of  the  pa- 
pillary surface  of  the  tongue,  and  are  about  nine  in  number, 
though  they  are  frequently  fewer,  and  sometimes  more.  They 
are  disposed  in  two  oblique  rows,  which,  by  converging  back- 
wards, meet  and  generally  form  something  like  the  letter  V. ;  the 
fifth  papilla  being  the  angle  of  the  figure.  Each  of  these  bodies 
resembles  a  cone  standing  upon  its  summit,  and  is  surrounded  by 
a  circular  fossa  which  permits  it  to  project  but  inconsiderably 
above  the  general  level  of  the  tongue.  Sometimes  two  or  more 
are  in  the  same  fossa.  The  Papilla?  Mediae,  or  Fungiformes,  are 
more  numerous  than  the  last,  and  next  to  them  in  size;  they 
are  enlarged  at  their  loose  end  into  a  sort  of  rounded  head, 
whence  their  name;  they  are  irregularly  scattered  over  the 

*  This  doubling  also  exhibits,  occasionally,  a  small  muscle  inserted  into  its  base, 
and  arising  from  the  upper  constrictor  of  the  pharynx,  and  which  has  the 
effect  of  widening  the  pouch. 


MUCOUS  COVERING  OF  THE  TONGUE.  497 

tongue.  Those  which  are  next  in  size  and  still  more  abundant, 
are  the  Papillae  Villosse.  The  Papillae  Filiformes  fill  up  the  in- 
tervals of  the  others,  are  the  smallest,  and  are  found,  principally, 
near  the  middle  of  the  tongue  and  at  its  front  extremity. 

Most  commonly  the  central  papilla  maxima  has  the  largest 
fossa  of  any.of  that  class,  and  which  is  designated  by  the  term 
foramen  ccecum.  A  little  behind  this  foramen  there  is  frequent- 
ly another,  called  the  same  by  some  anatomists,  but  not  fur- 
nished with  a  papilla,  into  which  some  mucous  follicles  discharge 
their  contents:  from  time  to  time  it  has  been  fallaciously  consi- 
dered as  receiving  the  excretory  duct  of  the  thyroid,  or  of  some 
of  the  salivary  glands. 

The  papillae  of  the  tongue,  though  they  vary  in  their  shape 
and  size,  have  very  much  the  same  structure  in  regard  to  the 
abundance  of  blood  vessels  and  nerves  which  enter  into  their 
composition.  When  uninjected,  and  viewed  with  the  naked  eye, 
their  surface  appears  smooth,  but  when  made  turgid  by  injection, 
they  are  covered  with  little  asperities  or  filaments,  which  seem  to 
be  formed  principally  of  blood  vessels,  having  a  very  tortuous  and 
superficial  course;  forming  loops,  or  doublings,  in  projecting  on 
the  surface  of  the  papilla,  and  anastomosing  freely  with  each 
other.*  Besides  vessels,  there  is  a  soft  whitish  substance,  sup- 
posed to  be  nervous,  entering  into  the  composition  of  each  fila- 
ment. The  larger  papilla?  on  the  back  part  of  the  tongue  are 
supplied  by  the  glosso-pharyngeal  nerve,  and  the  papillae  on  its 
front  part  by  the  trigeminus  or  fifth  pair. 

The  surface  of  the  tongue  between  the  papilla?  maximae  and 
the  os  hyoides  is  destitute  of  papillae,  and  is  covered  only  by  the 
common  mucous  membrane  of  the  mouth,  having  beneath  it  many 
muciparous  glands,  which  in  different  individuals  produce  promi- 
nences more  or  less  elevated,  and  are  of  a  lenticular  shape  with 
a  diameter  of  a  line  or  two.  Their  orifices  are  very  visible,  and 
easily  receive  a  large  bristle. 

The  Epidermis,  which  is  found  upon  all  other  parts  of  the  lining 
membrane  of  the  mouth,  is  also  continued  over  the  whote  upper 
surface  of  the  tongue,  and  consequently  invests  each  papilla;  it 
is  called  there  Peri-glottis.  It  is  soft  and  humid,  may  be  detached, 
by  maceration,  and  is  frequently  detached  in  fevers.  On  its  up- 

*  Soemmering,  Anat.  J.  Cloquet.  pi.  cxix. 
42* 


498  ORGANS   OF  DIGESTION. 

per  surface,  it,  when  detached,  will  have  many  elevations;  while 
on  the  lower  there  will  be  corresponding  excavations,  which  to 
superficial  observation  give  it  the  appearance  of  being  cribri- 
form. 

The  tongue  is  supplied  with  arteries,  principally  from  the  lin- 
gual branch  of  the  carotid,  and  with  nerves  from  the  hypo-glos- 
sal, the  fifth  pair,  and  the  glosso-pharyngeal.  The  former  is 
supposed  to  be  exclusively  appropriated  to  its  muscular  move- 
ments, and  the  two  latter  to  its  sensations.  Its  faculty  of  taste 
seems  to  be  most  active  at  the  tip;  on  the  sides,  and  near  the 
middle,  behind,  it  is  inconsiderable.  The  soft  palate  seems  also 
to  participate  in  the  function  of  taste. 


CHAPTER  IV. 

OF  THE  PALATE. 

THE  Palate  (Palatum)  is  composed  at  its  anterior  part  of  the 
palatine  processes  of  the  superior  maxillary  and  palatine  bones, 
covered  above  by  the  pituitary  membrane,  and  below  by  the 
lining  membrane  of  the  mouth.  This  portion  of  it  is  the  hard 
palate,  and  separates  the  mouth  from  the  nose.  Behind  it  is  a 
membranous  portion  called  the  soft  palate,  which  separates  par- 
tially the  mouth  from  the  upper  part  of  the  pharynx. 

That  part  of  the  lining  membrane  of  the  mouth  which  covers 
the  hard  palate,  has  a  hard  cartilaginous  feel,  and  is  not  so  vas- 
cular or  sensible  as  other  parts.  It  has  a  ridge  in  its  centre  just 
beneath  the  middle  palate  suture,  and  from  each  side  of  it  there 
are  transverse  ridges  extending  to  the  alveolar  processes.  This 
arrangement  is  more  evident  at  its  anterior  part,  and  in  middle- 
aged  persons;  in  the  old  it  is  faint,  and  frequently  does  not  exist 
when  the  alveoli  are  gone.  Beneath  this  membrane,  particular- 
ly at  its  posterior  part,  the  muciparous  glands  are  very  abundant 
and  closely  set  against  each  other,  so  as  to  form  a  perfect  layer, 
extending  itself  upon  the  front  of  the  soft  palate,  and  making  one 
half  of  its  thickness. 

The  Soft  Palate  (Velum  Pendulum  Palati)  has  on  oblong  shape, 


MUSCLES  OF  THE  PALATE.  499 

and  being  continued  from  the  posterior  margin  of  the  hard  pa- 
late, it  is  stretched  across  the  back  of  the  mouth  from  one  side  to 
the  other,  and  obliquely  downwards  and  backwards.  Its  inferior 
margin,  which  is  free,  offers  in  its  centre  a  projection  of  half  an 
inch  or  three  quarters  in  length,  which  is  the  Uvula.  From  each 
side  of  the  latter  there  proceed  two  crescentic  doublings  of  the 
lining  membrane  of  the-  mouth,  called  the  lateral  half  arches  of 
the  palate. 

The  Anterior  Half  Arch  is  more  distinct  than  the  other,  and 
arising  at  the  side  of  the  uvula  by  one  end,  terminates  by  the 
other  in  the  side  of  the  base  of  the  tongue  on  a  line  with  the 
papillse  maximse. 

The  Posterior  Half  Arch  arises  from  the  side  of  the  uvula  near 
the  last,  and  diverging  from  it  backwards,  and  outwards,  has  the 
other  end  lost  gradually  in  the  lining  membrane  of  the  pharynx 
near  its  middle.  In  the  depression  between  these  duplications, 
on  either  side,  is  the  Tonsil  Gland.  The  space  bounded  in  front 
and  behind  by  these  lateral  half  arches  is  the  Fauces,  and  the 
anterior  opening  into  it,  is  the  Isthmus  of  the  Fauces. 

When  the  mucous  membrane  of  the  soft  palate  is  removed,  its 
muscles  are  exposed,  and  are  as  follow : — 

1.  The  Constrictor  Isthmi  Faucium  is  a  small  fasciculus  of 
fibres,  on  each  side,  within  the  duplicature  of  the  anterior  lateral 
half  arch.     It  arises  from  the  middle  of  the  soft  palate  near  the 
base  of  the  uvula,  and  is  inserted  into  the  side  of  the  tongue  near 
its  root  in  a  line  with  the  papillae  maxima?. 

It  tends  to  close  the  opening  between  the  mouth  and  the  pha- 
rynx. 

2.  The  Palato-Pharyngeus  is  also  a  small  fasciculus,  within 
the  duplicature  forming  the  posterior  lateral  half  arch.     It  arises 
from  the  middle  of  the  soft  palate  near  the  base  of  the  uvula, 
and  is  inserted  into  the  pharynx  at  the  space  between  the  mid- 
dle and  lower  constrictors,  behind  the  stylo-pharyngeus,  and  into 
the  superior  posterior  margin  of  the  thyroid  cartilage.   It  spreads 
itself  out  considerably,  so  as  to  cover,  along  with  the  stylo-pha- 
ryngeus, almost  the  whole  lateral  portion  of  the  pharynx  to  its 
lower  part. 

It  draws  the  soft  palate  downwards. 


500  ORGANS  OF  DIGESTION. 

3.  The  Circumflexus,  or  Tensor  Palati,  is  behind  the  pterygoid 
process  of  the  sphenoid  bone.     It  arises  from  the  spinous  process 
of  the  latter  behind  the  foramen  ovale,  and  from  the  contiguous 
part  of  the  Eustachian  tube;  it  then  passes  downwards  in  con- 
tact with  the  pterygoideus  internus  muscle,  and  terminates  in  a 
broad  tendon  below,  which  winds  around  the  hook  of  the  inter- 
nal pterygoid  process,  and  is  inserted  into  the  soft  palate  near 
its  middle,  and  into  the  posterior  lunated  edge  of  the  palate 
bone. 

It  spreads  out  or  extends  the  palate. 

4.  The  Levator  Palati  is  on  the  inner  side  of  the  last.     It 
arises  from  the  point  of  the  petrous  bone,  and  from,  the  contigu- 
ous part  of  the  Eustachian  tube,  and  passes  downwards  to  be 
inserted  into  the  soft  palate.     This  muscle,  in  the  dissection  of 
the  pharynx  may  be  seen  between  its  external  edge,  and  the  pte- 
rygoideus internus  muscle. 

It  draws  the  soft  palate  upwards. 

5.  The  Azygos  Uvulae  is  in  the  centre  of  the  soft  palate  and 
of  the  uvula.     It  arises  from  the  posterior  pointed  termination  of 
the  middle  palate  suture,  and  goes  down  into  the  uvula. 

It  draws  the  uvula  upwards,  and  diminishes  the  vertical 
breadth  of  the  soft  palate. 

When  the  mucous  membrane  is  removed,  the  upper  constric- 
tor of  the  pharynx  appears  between  the  anterior  and  the  poste- 
rior half  arches. 


CHAPTER  V. 

OF  THE  GLANDS  OF  THE  MOUTH. 

THESE  glands  consist  in  such  as  are  muciparous,    and    in 
such  as  are  salivary. 

SECT.   I. MUCIPAROUS  GLANDS. 

These  glands  (GlandulcB  Muciparce)  are  whitish,  somewhat 
oval  and  flattened,  and  are  from  the  fraction  of  a  line  to  two 


SALIVARY  GLANDS.  501 

lines  in  diameter:  they  are  found  in  great  abundance  beneath  the 
lining  membrane  of  the  mouth  at  several  places,  to  wit:  on  the 
lips,  (Gland.  Labiales;)  on  the  cheeks,  (Gland.  Buccales;)  and 
also,  as  mentioned,  at  the  posterior  part  of  the  upper  surface  of 
the  tongue,  (Gland.  Mucip.  Linguce.)  The  layer  of  them,  (Gland. 
Palatines,,)  which  is  found  at  the  posterior  part  of  the  hard  palate, 
is  also  continued  over  the  anterior  and  the  posterior  surface  of 
the  soft  palate,  especially  the  anterior  surface. 

The  Tonsils,  (Tonsillce,MmygdaIce,)  situated,  as  observed,  one  on 
each  side,  between  the  half  arches  of  the  palate,  are  six  or  eight 
lines  long,  four  or  five  wide,  and  about  three  thick.  They  are 
rather  a  collection  of  large  mucous  follicles,  than  a  congeries  of 
glandular  bodies,  in  consequence  of  which  their  surface  is  very 
much  reticulated.  Owing  to  their  being  placed  upon  the  upper 
constrictor  of  the  pharynx,  their  mobility  is  very  striking  and 
considerable. 

A  great  many  small  pores  are  observed  on  the  internal  sur- 
face of  the  mouth,  which  are  the  orifices  of  the  ducts  of  the 
muciparous  glands. 

SECT*  II.— SALIVARY  GLANDS. 

On  either  side  of  the  neck,  bordering  upon  the  mouth,  there 
are  three  glandular  bodies  for  the  secretion  of  saliva;  they  are 
the  parotid,  the  submaxillary,  and  the  sublingual.  The  fluid  se- 
creted from  them  is  of  great  service  in  digestion,  and  is  blended 
with  the  food  in  mastication,  and  in  swallowing.  According  to 
Berzelius,  it  has  a  considerable  affinity  to  oxygen;  and  consists 
in  a  white  mucous  substance,  holding,  in  a  state  of  solution,  the 
saline  articles  usually  found  in  the  serum  of  the  blood. 

The  Parotid  Gland  (Glandula  Parotis,)  is  the  largest  of  the 
three,  and,  like  the  others,  is  of  a  light  pink  colour.  Owing  to 
he  space  into  which  it  is  crowded,  it  is  o  a  very  irregular  figure. 
It  fills  up  the  cavity  on  the  side  of  the  head  between  the  mastoid 
process  and  the  ramus  of  the  lower  jaw,  extending  beyond  the 
edge  of  the  latter  so  as  to  cover  the  posterior  margin  of  the  mas- 
seter  muscle.  It  is  somewhat  pointed  at  its  fore  part.  Its  ver- 
tical length  reaches  from  the  zygoma  above,  to  the  angle  of  the 
jaw  below;  sometimes,  indeed,  a  little  lower  down.  In  thick- 


502  ORGANS  OF  DIGESTION. 

ness  it  extends  from  the  integuments  externally,  to  the  styloid 
process,  the  styloid  muscles,  and  the  tendon  of  the  digastricus, 
internally,  being  there  only  separated  from  the  internal  carotid 
artery  by  these  parts.  It  is  traversed  from  behind  forwards  by 
the  portio-dura  nerve,  and  from  below  upwards  along  its  inter- 
nal margin  by  the  external  carotid  artery  and  the  temporal  vein. 

This  gland  has  no  appropriate  capsule,  but  being  covered,  on 
its  external  face,  by  the  continuation  of  the  fascia  superficialis 
of  the  neck,  prolongations  are  sent  from  the  fascia  which  pene- 
trate it  in  every  direction,  and  keep  its  lobules  together. 

Its  duct  (Ductus  Stenonianus)  departs  from  its  anterior  edge 
a  few  lines  below  the  zygoma,  and  traverses  the  outer  face  of 
the  masseter  muscle,  in  a  line,  according  to  the  observations 
of  Dr.  Physick,  drawn  from  the  lobe  of  the.  ear  to  the  end  of 
the  nose.  It  is  about  the  size  of  a  crow  quill,  is  hard  and  ten- 
dinous, with  thick  parietes.  It  lies  close  to  the  masseter  mus- 
cle, and  at  the  anterior  edge  of  the  latter  penetrates  a  pad  of 
fat  commonly  found  there  on  the  side  of  the  cheek;  it  then 
perforates  the  posterior  end  of  the  buccinator,  so  as  to  have 
its  oral  orifice  opposite  the  second  large  molar  tooth  of  the  up- 
per jaw.  On  opening  the  mouth  wide  during  a  state  of  fast- 
ing, a  jet  of  saliva  will  sometimes  indicate  the  position  of  this 
orifice. 

A  small  gland  (Gland.  Accessoria  Parotidis)  is  sometimes  found 
between  this  duct  and  the  zygoma;  it  varies  in  form  and  size, 
and  has  a  distinct  excretory  canal  discharging  itself  into  the 
parotid  duct, 

The  Submaxillary  gland  (Glandula  Submaxillaris)  is  not  more 
than  a  third  or  one  half  the  size  of  the  last,  and  has  a  more  re- 
gular form  in  being  somewhat  ovoidal.  It  is  accommodated 
in  the  depression  on  the  side  of  the  neck  formed  by  the  body 
of  the  lower  jaw  externally,  by  the  mylo-hyoideus  muscle 
above,  and  by  the  tendon  of  the  digastric  below.  The  platys- 
ma  myodes  intervenes  between  it  and  the  skin.  It  almost 
touches  the  parotid  gland  behind,  being  separated  from  it  only 
by  a  process  sent  in  from  the  fascia  superficialis,  and  continu- 
ous with  the  ligament,  going  from  the  styloid  process  to  the 
ramus  of  the  lower  jaw.  As  it  extends  to  the  posterior  margin 
of  the  mylo-hyoideus  muscle,  it  there  touches  the  sublingual 


SALIVARY  GLANDS.  503 

gland.     The  facial  artery  either  passes  through  it  or  is  very 
much  connected  with  it. 

Its  colour  and  appearance  are  the  same  with  the  parotid; 
but  its  lobules  are  more  easily  separated,  as  they  are  held  to- 
gether only  by  weak  cellular  substance,  which  forms  a  sort  of 
capsule  to  them.  Its  duct,  (Ductus  Whartonianus,)  which  is 
single,  comes  from  the  assembling  and  junction  of  branches 
from  the  several  lobes.  It  is  much  thinner,  more  extensible, 
and  larger  in  proportion  than  the  parotid  duct;  and  being  di- 
rected backwards,  winds  over  the  posterior  edge  of  the  mylo- 
hyoid  muscle,  in  order  to  get  to  the  cavity  of  the  mouth.  It 
then  passes  along  the  internal  face  of  the  sublingual  gland,  be- 
low the  tongue,  and  terminates  by  a  small  projecting  orifice  on 
the  anterior  margin  of  the  frsenum  linguae. 

A  continuation  of  the  substance  of  this-  gland,  of  a  few  lines 
in  thickness,  described  by  Bartholin,  is  found  at  the  posterior 
end  of  the  sublingual  gland,  and  has  its  excretory  duct  some- 
times opening  at  the  side  of  the  duct  of  Wharton,  and,  on  other 
occasions,  into  one  of  the  ducts  which  issue  from  the  sublin- 
gual gland.  When  this  common  duct  exists,  it  is  called  the 
canal  of  Bartholin,  (Ductus  Bartholinianus,)  who  first  discovered 
it  in  the  lion,  in  1684. 

The  Sublingual  Gland  (Glandula  Sublingualis)  is  an  oblong 
body,  covered  by  the  lining  membrane  of  the  mouth,  but  visible 
when  the  tongue  is  turned  up.  It  is  placed  above  the  mylo- 
hyoid  muscle,  along  the  under  surface  of  the  tongue,  and  is 
readily  distinguished  by  its  ridged  unequal  surface,  projecting 
into  the  mouth.  It  is  not  so  large  as  the  submaxillary  gland. 

Its  lobules  are  smaller  than  those  of  the  preceding  gland,  and 
are  also  whiter  and  harder.  Instead  of  having  but  one  excreto- 
ry duct,  it  has  several;  sometimes  fifteen  or  twenty  of  them  are 
discernible:  on  other  occasions,  several  of  them  are  collected 
into  one  or  two  principal  trunks,  (Ductus  Riviniani,)  and  open 
either  directly  into  the  mouth,  or  into  the  duct  of  Wharton. 
These  several  openings  are  found  along  the  bottom  of  the 
mouth,  on  either  side  below  the  tongue.  Several  small  saliva- 
ry granulations  or  glands  border  on  the  sublingual. 

The  position  of  the  salivary  glands  is  such,  that  they  are 
much  moved  and  pressed  upon  by  the  neighbouring  parts  in 


504  ORGANS  OF  DIGESTION. 

mastication,  independently  of  the  emission  of  their  fluid  being 
provoked  by  hunger.  Owing  to  the  similitude  of  their  struc- 
ture, and  to  their  not  being  regularly  supplied  like  other  glands 
with  capsules,  their  limits  are  occasionally  so  inexactly  traced, 
that  they  continue  into  each  other  by  adjacent  points,  and  form 
thus  an  uninterrupted  chain.* 

They  all  are  of  the  conglomerate  kind,  or,  in  other  words,  con- 
sist in  a  congeries  of  smaller  glands  or  lobes  and  lobules.  They 
are  well  furnished  with  arteries;  which  are  branches,  from  the 
external  carotid,  and  go  in  several  trunks  instead  of  in  a  lead- 
ing one.  The  parotid  is  commonly  supplied  by  trunks  coming 
directly  from  the  external  carotid,  the  submaxillary  is  supplied 
from  the  facial  artery,  and  the  sublingual  gland  from  the  lin- 
gual artery.  Their  nerves  come  from  the  fifth  pair,  and  from 
the  portio  dura. 

The  retrograde  injection  of  their  excretory  ducts  shows  how 
the  latter  are  formed  by  the  assembling  of  branches  from  the 
different  lobules.  These  ducts  consist  of  two  coats,  a  fibrous 
one  externally,  and  a  mucous  one  internally. 


CHAPTER  VI. 

OF  THE  PHARYNX  AND  (ESOPHAGUS. 
SECT.  1. — OF  THE  PHARYNX. 

THE  Pharynx  (Pharynx)  is  a  large  membranous  cavity, 
placed  between  the  cervical  vertebrae  and  the  posterior  part  of 
the  nose  and  mouth.  It  extends  from  the  base  of  the  cranium 
to  the  lower  part  of  the  cricoid  cartilage,  or  to  the  lower  part 
of  the  fifth  cervical  vertebra.  It  is  in  contact,  behind,  with 
the  vertebrae  and  the  muscles  lying  upon  them,  being  simply 
attached  there  by  loose  cellular  substance;  above,  it  adheres 
to  the  cuneiform  process  of  the  os  occipitis,  and  to  the  point  of 
the  petrous  portion  of  the  temporal  bones;  in  front,  to  the  pos- 
terior part  of  the  upper  and  of  the  lower  maxilla  near  the  ter- 

*  Bichat,  Anat  Descrip.  vol.  v.  p.  24. 


THE  PHARYNX.  505 

mination  of  their  alveolar  processes,  to  the  cornua  of  the  os 
hyoides,  the  side  of  the  thyroid  and  of  the  cricoid  cartilage; 
and  below  it  is  continued  into  the  oesophagus.  In  consequence 
of  these  several  attachments  the  pharynx  is  kept  open,  or,  in 
other  words,  its  sides  are  prevented  from  collapsing,  and  it  is 
drawn  up  and  down  in  the  motions  of  the  tongue  and  of  the 
larynx. 

The  Pharynx  consists  in  three  coats:  an  external  one,  formed 
by  three  muscles,  on  each  side,  one  above  the  other,  and  called 
constrictors;  an  intermediate  cellular' coat;  and  an  internal  mu- 
cous one. 

1.  The  Musculus  Constrictor  Pharyngis  Inferior,  arises  from 
the  side  of  the  cricoid,  and  from  the  whole  length  of  the  side  of 
the  thyroid  cartilage.     From  these  points  its  fibres  diverge  to 
the  middle  vertical  line  on  the  back  of  the  pharynx,  where  they 
join  with  their  congeners  of  the  opposite  side.     The  lower 
fibres  are  nearly  if  not  completely  horizontal,  and  those  above 
increase  successively  in   their  obliquity  upwards,  so  that  the 
upper  ones  are  extremely  oblique,  and  reach,  at  their  termina- 
tion, to  within  twelve  or  fourteen  lines  of  the  upper  part  of  the 
pharynx. 

2.  The  Constrictor  Pharyngis  Medius,  arises  from  the  cornu 
and  appendix  of  the  os  hyoides,  and  from  the  ligament  connect- 
ing the  posterior  end  of  the  latter  with  the  upper  cornu  of  the 
thyroid  cartilage.     Its  inferior  margin  is  overlapped  by  the  su- 
perior margin  of  the  last;   its  fibres  there  are  also  horizontal, 
and,  indeed,  somewhat  convex  downwards;  while  the  superior 
fibres  become  successively  more   oblique  in  ascending.     It  is 
inserted  by  the  middle  line  behind,  into  its  fellow  of  the  oppo- 
site side,  and  by  its  point  above  into  the  cuneiform  process  of 
the  os  occipitis,  just  in  advance  of  the  recti  majores  muscles. 

3.  The  Constrictor  Pharyngis  Superior,  arises  from  the  ptery- 
goid  processes  of  the  sphenoid  bone,  at  their  lower  end ;  and 
below  them  from  the  back  part  of  the  upper  and  under  jaws  be- 
hind the  last  molar  teeth,  it  is  also   connected   at  its  anterior 
margin  with  the  buccinator  muscle,  and  with  the  root  of  the 
tongue  between  the  anterior  and  the  posterior  half  arches  of 

VOL.  I.— 43 


506  ORGANS  OF  DIGESTION. 

the  palate,  being  blended  there  with  the  transverse  fasciculus  of 
the  stylo-glossus  muscle.  It  has  its  lower  edge 'overlapped  by 
the  constrictor  medius ;  and  its  fibres  are  more  horizontal,  ge- 
nerally, than  those  of  the  preceding  muscles.  It  is  inserted 
into  its  fellow  by  a  middle  line,  the  upper  end  of  which  adheres 
to  the  cuneiform  process  of  the  os  occipitis.  The  superior 
margin  of  this  muscle  between  the  pterygoid  process  of  the 
sphenoid,  and  the  cuneiform  process  of  the  occipital  makes  a 
crescentic  line,  the  concavity  of  which  is  upwards. 

The  constrictor  muscles  of  the  pharynx,  by  their  successive 
contraction,  convey  the  food  from  the  mouth  into  the  oeso- 
phagus. 

The  Stylo-Pharyngeus,  which  is  mentioned  among  the  mus- 
cles of  the  neck,  forms  an  interesting  portion  of  the  structure 
of  the  pharynx,  and  may  be  considered  on  a  footing  with  the 
longitudinal  fibres  of  the  oesophagus  and  of  the  intestines;  being 
intended  to  shorten  the  pharynx  by  arising  from,  or  having  a 
fixed  point  at  the  styloid  process  above,  and  by  being  jotned 
into  the  pharynx  below.  Its  fibres  being  first  of  all  on  the  out- 
side of  the  upper  constrictor,  are  readily  traced  between  the 
lining  membrane  and  the  two  lower  constrictors  to  the  poste- 
rior margin  of  the  thyroid  cartilage ;  into  which,  after  spread- 
ing out  considerably,  they  are  finally  inserted. 

The  intermediate  membrane  of  the  pharynx  is  merely  con- 
densed cellular  tissue,  which  joins  the  muscular  to  the  mucous 
coat. 

The  internal  or  mucous  membrane  of  the  pharynx,  which 
lines  the  last,  is  spread  uniformly  over  it;  the  only  irregularity 
of  its  surface  being  made  by  the  presence  of  mucous  follicles 
and  glands,  which  are  more  abundant  above  between  the  pos- 
terior margins  of  the  two  slylo-pharyngei  than  below.  It  is 
covered  by  a  very  delicate  epidermis,  and  is  supplied  with  two 
arteries  on  each  side,  the  superior  and  inferior  pharyngeal,  the 
first  of  which  cornes  from  the  internal  maxillary,  and  the  se- 
cond from  the  external  carotid.  It  exhibits  a  number  of  small 
veins,  which  run  into  the  internal  jugular  or  some  of  its 
branches. 


(ESOPHAGUS.  507 

The  shape  of  the  cavity  of  the  pharynx  is  oblong  and  cylin- 
drical, being  somewhat  larger  at  its  superior  end]  at  the  latter 
place,  where  it  is  attached  to  the  petrous  bone,  it  presents  a 
deep  corner,  which  gives  it  a  square  appearance  there,  and  has 
a  collection  of  muciparous  follicles  somewhat  like  the  tonsil 
gland.  Anteriorly,  and  above,  it  is  continuous  with  the  Eusta- 
chian  tubes,  and  with  the  posterior  nares;  just  below  this,  with 
the  fauces  and  mouth,  and  below  the  root  of  the  tongue  with 
the  cavity  of  the  glottis  or  larynx.  At  its  lower  extremity, 
where  it  terminates  in  the  oesophagus,  it  is  so  contracted  as  to 
suit  the  size  of  the  latter  cavity. 


SECT.  II. OP   THE  (ESOPHAGUS. 

The  ossophagus  is  the  tube  just  i-n  front  of  the  spine  and  be- 
hind the  trachea,  which  conducts  food  from  the  pharynx  into 
the  stomach.  When  inflated  it  is  of  a  cylindrical  shape,  about 
ten  or  twelve  lines  in  diameter :  it  is  nine  or  ten  inches  long, 
and  gradually  increases  in  its  size  from  above  downwards:  in 
its  state  of  repose  it  is  flattened  from  before  backwards.  Its 
descent  is  not  entirely  vertical,  but  at  the  lower  part  of  the 
neck  it  inclines  somewhat  to  the  left  of  the  middle  line,  and  is, 
therefore,  rather  to  the  left  side  of  the  trachea  than  behind  it. 
It  passes  down  the  thorax  in  the  posterior  mediastinum,  being 
bounded  on  its  left  side  by  the  aorta,  and  on  the  right  by  the 
vena  azygos.  It  keeps  during  the  early  part  of  its  course  in 
this  cavity,  in  front  of  the  middle  line  of  the  spine;  but  lower 
down  it  inclines  again  slightly  to  the  left  side,  in  front  of  the 
aorta,  in  order  to  reach  the  cesophageal  orifice  of  the  diaphragm, 
through  which  it  penetrates  into  the  abdomen.  In  all  this  pas- 
sage the  oesophagus  is  united  to  adjacent  parts  by  a  loose  cel- 
lular tissue. 

The  oesophagus  is  composed  of  three  coats:  the  muscular; 
the  cellular  or  nervous;  and  the  mucous. 

The  muscular  coat  is  the  external,  and  very  strong.  It  con- 
sists in  two  well  marked  lamina?  of  muscular  fibres.  The  most 
exterior  is  the  thickest,  and  goes,  longitudinally,  from  one  end 
to  the  other  of  the  tube;  commencing,  according  to  J.  F. 
Meckel,  by  three  fasciculi  above;  one  of  which  arises,  tendi- 


508  ORGANS  OF  DIGESTION. 

nously,  from  the  posterior  face  of  the  cricoid  cartilage,  and  the 
other  two,  one  on  each  side,  from  the  inferior  constrictor  of 
the  pharynx.  These  fasciculi  descend  for  an  inch  or  two  be- 
fore they  spread  out  into  a  uniform  membrane.  The  internal 
muscular  lamina  consists  in  circular  fibres,  which  may  be  con- 
sidered as  a  continuation  of  the  lower  margin  of  the  inferior 
constrictor  of  the  pharynx,  and  are  either  horizontal  or  slightly 
spiral;  they  are  rather  deficient  on  the  fore  part  of  the  ceso- 
phagus  for  an  inch  at  its  superior  extremity.  Individually, 
their  length  is  short  of  the  circumference  of  the  ossophagus. 

_  r 

The  cellular  coat  is  next  in  order,  and  serves  to  unite  the 
muscular  and  the  mucous  together.  It  adheres  much  more 
closely  to  the  latter  than  it  does  to  the  former,  has  no  adipose 
matter  in  it,  but  is  found  to  be  abundantly  furnished,  more  par- 
ticularly towards  its  upper  end,  with  small  muciparous  glands; 
it  also  serves  to  transmit  the  blood  vessels  through  the  struc- 
ture of  the  oesophagus. 

The  mucous  coat  of  the  oesophagus  is  the  most  internal;  in 
the  undistended  state  it  always  presents  many  longitudinal 
folds,  going  from  one  end  to  the  other,  but  sometimes  blending 
with  each  other,  owing  to  the  contraction  of  the  circular  mus- 
cular fibres.  When  suspended  in  water  its  fine  villous  ap- 
pearance is  very  perceptible,  as  well  as  the  mucous  lacunae  or 
glands  which  open  upon  its  internal  surface.  As  it  is  a  conti- 
nuation of  the  mucous  membrane  of  the  pharynx,  it  has  the 
same  general  appearance,  but  is  rather  whiter.  Its  internal 
surface  is  also  covered  by  a  delicate  epidermis,  which  ceases 
at  the  cardiac  orifice  of  the  stomach,  and  may  be  raised  in 
shreds  by  maceration  and  by  boiling;  in  some  pathological 
conditions  this  epidermis  becomes  very  distinct  by  acquiring 
more  thickness  and  solidity,  than  what  belong  to  its  healthy 
state. 

The  arteries  of  the  oesophagus  are  derived  from  the  inferior 
thyroidal,  from  the  thoracic  aorta,  and  from  the  gastric.  Its 
nerves  come  principally  from  the  pneumogastric. 

END  OF  VOL.  I. 


INDEX    TO    VOX.    I. 


Page 

Abdominal  Fascia,    -  383 

Abdomen,  Muscles  of,    -  383 

Abductor  Pollicis  Pedis,        -  462 

Abductor  Min.  Digit.  Pedis,  -       .      -                                           463 

Abductor  Pollicis  Manus,  431 

Abductor  Indicis,  432 

Abductor  Min.  Digit.,  433 

Adductor  Pollicis  Pedis,  462 

Adductor  Metacarpi  Min.  Digiti,        -  433 

Adductores  Femoris,       -  -                                                         445 

Adductor  Pollicis  Manus,      -  -         432 

Alimentary  Canal,  -             -                              467 

Alveolar  Processes,  •         474 

Americans,  -                                        -                 177 

Annuli  Junct.  Ligamentosi,  -                                    424 

Anconeus,  419 

Ankle  Joint,  •.                                                 309 

Ankle,  Ligament  of,  440 

Aponeurosis  Plantaris,  441 

Aponeurosis  Palmaris,   -  -                                                          413 

Arm,  Muscles  of,  420 

Articulations,      -  -                                            251 

Articular  Cartilages,  -                                                  255 

Articulation  of  Wrist,      -  291 

Articulation,  Sterno-Clavicular,  283 

Astragalus,                         -~  -    -                              225 

Auricularis,  428 


Bones,  -  -  50 

Composition  of,  56 

Carpal,  -  193 

Growth  of,  71 

Individual,  ...  -  77 

Texture  of,  -----  52 

Vascularity  of,  -  <H 

Bi  cepsFlexor  Cubiti,                        -  416 

VOL.  I.— 44 


510  MTDEX. 

Page 

Biceps  Flexor  Cruris,  -                         -                                         451 

Bicorn  Ligament,.    -  -                                                  286 

Bordeu,               »  -             -                                                        320 

Brachialis  Interims,  -                                                              418 

Bursa  of  Fingers,  •                                                                    42& 

Buccinator,   -             -  -            ~,                       -                      368 


Callus,  -             -             -  -             -                 74 

Cartilages  of  Ribs,   -  112 

Carpus,  193 

Caucasian  Race,        -  174 

Cartilages,  251 

Cartilages,  Accidental,  253 

Calcis,    -  223 

Calcaneo-Scaphoid  Ligament,  -                                   311 

Carpal  Articulation,  -                           -                              291 

Calcaneo-Cuboid  Ligament,  312 

Cervical  Vertebrae,          *  80 

Cellular  Substance,  -  -                                                  3 17 
Cellular  Atmosphere,      - 

Cervicalis  Descendens,  406 

Clavicle,             -             -  -             -             -             -                186 

Coccyx, 

Coccygeal  Ligament, 

Compressor  Naris,   -             -  364 

Complexus, 

Conoid  Ligament,     -  '-                                   285 

Coracoid  Ligament,         -  -                          -               286 

Corrugator  Supercilii,  -                                                 366 

Coraco-Brachialis,           -  -             - 

Costo-Clavicular  Ligament,  284 

Cotyloid  Ligament,  299 

Cranium,      ------- 

Cranium,  Internal  Face  of,  158 

Cremaster,                  -  ...         389 

Crurseus,    ------  444 

Crucial  Ligaments,  -             -                                    304 

Cuboides, 226 

Cuneiform  Bones, 

Cutis  Vera,         -  ...                             330 

Cutis  Anserina,                       -  -            -                                   332 

Cuticula,              _._.-.  336 

Cyanosis,     -                           -  335 


Development  of  Skeleton,  67 

Dermoid  Covering,  -                                                             328 

Depressor  Labii  Sup.,    -  367 

Depressor  Anguli  Oris,  ....                      367 

Depressor  Labii  Inferioris,  -                                          368 


INDEX.  511 

Page 

Deltoldes,  414 

Dental  Cartilage,  -                        '  -                483 

Dental  Glands,          -  484 

Dentition,                          -  -                                                         484 

Dentition,  Irregularities  of    -  .-                                                 490 

Diaphysis,                        -  52 

Diploe,  -                                      156 

Digastricus,        -  -                                                         376 

Diaphragm,  -                                      394 

Digestion,  Organs  of,     -  -                467 

Dorsal  Vertebrae,  84 

Dutrochet,  333 

Elbow  Joint,  288 

Elain,     -                           -  -                                                           326 

Enamel,        -  -                                    474 

Epiphyses,          -----  52 

Epidermis,  -  336 

Ethmoides,         -             -  -                           -                              135 

External  Cellular  Tissue,      -  -         320 

Extensor  Carp.  Had.  Long.,  -             -                                           426 

Brev.  Digit.  Pedis,  -             -             -             -         460 

Carpi  Ulnaris,  427 

Carp.  Rad.  Brev.,  -         426 

Digit.  Com.,    -  -                                                         428 

Long.  Digit  Pedis,  ...                       453 

Metacarpi  Pollicis,  -                                                         428 

Pollicis  Minor,  et  Major,   -  429 

Prop.  Poll.  Pedis,  454 


Facial  Angle,            -  172 
Face,     -------       138,  169 

Fat,               -                                        -  325 

Fascia  Superficial  Colli,  371 

Fascia  Superficialis  Abdominis,  383 

Fascia  Profunda  Colli,    -  373 

Fascia  Transversalis,             -             -  390 

Fascia  Iliaca,      ------  339 

Fasciae  of  Lower  Extrem.,   -  436 

Fasciae  of  Upper  Extrem.,                                      -  411 
Fascia  Lata,               -                                          ...         435 

Fasciae  of  Foot,                             r  446 

Fascia  Cruralis,                       -                          -  439 

Femoral  Bone,   -  213 

Fibro-Cartilage,        ....  256 

Fibula, 220 

Finger  Joints,           -----  298 

Fingers,                           -             -             -            -             -  199 

Flexor  Carpi  Radialis,                                      -  420 

Flexor  Carpi  Ulnaris,     -                          -            -            -  421 


512  INDEX. 

Pago 

Flexor  Digitorum  Subl.,  -                                                              422 

Flexor  Digit.  Profund.,  -  -                                          422 

Flexor  Brev.  Poll.  Manns,  -                                                                432 

Flexor  Parv.  Min.  Digit ,  -                                                       433 

Flexor  Long.  Digit.  Pedis,  -                                                              458 

Flexor  Long.  Poll.  Pedis,  459 

Flexor  Brev.  Digit.  Pedis,  461 

Flexor  Brev.  Poll.  Pedis,  462 

Flexor  Min.  Digit,  Pedis,  -                                                                463 
Flexor  Accessorius, 
Flexor  Pollicis  Longus, 

Foot,  Motions  of,  244 

Foot,  Bones  of,        -  223 

Foot,  Muscles  of,  460 

Foot,  Articulations  of,  310 

Fontanels,  179 

Fore  Arm,  Motions  of,  207 

Fore  Arm,  Muscles  of,    -  420 

Fore  Arm,  Articulations  of,  291 

Prenuiae  of  Mouth,  470 

Frontal  Bone,           .....  124 


Gagliardi  on  Bones,        -  58 

Gaultier,  ...                         -             -         333 

Gastrocnemius,  -  456 

Genio-Hyoideus,  -                                                                           378 

Gemini,  -                                                                       449 

Glenoid  Ligament,  -                           -                                                  288 

Glutseus  Magnus,  447 

Glutaeus  Minimus,  - 

Glutaeus  Medius,  448 

Gracilis,  445 

Gums,    -             -  ...                                          478 


Hairs,    -                           -  -                                                         344 

Half  Arches,  of  Palate,  499 

Hand,  Muscles  of,  430 

Hand,  Motions  of,    -  -                                   210 

Hand,  Bones  of,  -                                       -               193 
Head,  Development  of  Fretal, 

Head,  External  Surface  of,  -                                                         161 

Head,            -  .            ^             -             -                       121 

Key's  Ligament,  -             -                                          438 

Hip  Joint,                 ...  299 

Hunter,-                           -  -                                                          337 
Humeral  Bone, 

Hyoides,            -            •  »                         -            »               18i 


INDEX,  513 

Page 

Ilium,                         -  97 

Iliacus  Interims,  -                399 

Ilio  Lumbar  Ligament,  -                                    275 

Innominata,         -             -  -                 97 

Inter  vertebral  Substance,  *                      266 

Inferior  Extremities,       -  213 

Inf.  Extremities  in  Standing,             -  235 

Inf.  Extremities  in  Locomotion,  -       241,  246 

Inf.  Palmar  Ligaments,  297 

Inter-Clavicular  Ligament,-  283 

Integuments,  -                                   317 

Internal  Cellular  Tissue,  322 

Intercostal  Muscles,  382 

Inter-Trans  versarii,  410 

Infra-Spinatus,           -             -             -  -             -             -415 

Indicator,                          ...  -                430 

Interosseal  Lig.  of  Fore  Arm,  -        290 

Interosseous  Ligament  of  Leg,    -  308 

Interosseous  Muscles  of  Hand,  434 

Interosseous  Muscles  of  Foot,     -  -                             464 

Inter-Spinales,                                      -  410 

Itinera  Dentium,  487 

Ischium,      -            -             -             -  -             -                      100 

Joints,    -  260 

Knee  Joint,  -  302 

Latissimus  Dorsi,                   -             -  -            -                      401 

Lateral  Lig.  of  Knee,    ,  -  304 

Laeerti,  of  Muscles,  350 

Leg,  Motions- of,                          -  243 

Levator  Anguli  Oris,  366 

Levator  Labii  Sup.,         -  -                366 

Levator  Labii  Inferioris,  -                       368 

Leg,  Muscles  of,             -  452 

Levator  Scapulas,      -  403 

Levatores  Costarum,       -  -                410 
Ligamentous  Tissue,              .....         257 

Ligaments,  Yellow,         -  -                             269 

Ligament.  Alare,       -  -                       307 

Ligament.  Mucosum,      -  -                                           307 

Lig.  Carpi  Volare,  413 
Lig.  Carpi  Dorsale, 
Ligamenta  Vaginalia,             .... 

Lips,      -                          470 

Little  Toe,  Muscles  of,  -                      463 

Longus  Colli,     ------  378 

Longissimus  Dorsi,                ...  -            -        405 

44* 


514  INDEX. 

Page 

Lower  Jaw,  Articulations  of,  •             -            -                            263 

Lower  Extremities,  Joints  of,  .  *  •"                                   -        299 

Lumbar  Vertebrae,  -                              85 
Lumbricales  Pedis, 

Lumbricales,       -            -   '  -                                       -               431 


Malar  Bones,      -  •  *-             -             -             -                144 

Maxillare  Inferius,    -  -'  !                                    -             -         146 

Maxillare  Superius,  -                138 

Masseter,     -             -  -                           *    '         -         369 

Medulla,             -  ...            -         £jtf\         -                 65 

Metacarpal  Joints,     -  295 

Metacarpus,         -  -                       .. . .-y«             197 

Metatarsus,                -  .   -   _         -             -             -             -         229 

Metatarsal  Joints,  -.                                           315 

Membrana  Musculorum,        -  350 

Middle  Straight  Ligament,  273 

Moderator  Ligament,  272 

Mongolian  Race,  -                           ».                                          174 

Mouth,                      -  469 

Mouth,  Glands  of,  -             -  '           -             -            -               50° 

Muciparous  Glands,  500 

Multifidus  Spinas,  408 
Muscles,  General  Anatomy  of, 

Muscles  of  the  Back,  -                                                              i      400 

Muscular  Fibre,        -  -             -             -                      351 

Muscular  Motion,  -                           -                             355 

Mylo-Hyoideus,       -  -                                   377 


Nasal  Bones,  -             -             -             -            '*>:                          142 

Nails,            -  -             -             -             -             -       ^     -         342 

Negroes,  -                             174 

"Nose,            -  -             -             -             -             -             -         1G5 


Obliquus  Ext.  Abdominis,  <• 

Obliquus  Int.  Abdominis,    -  386 

Obliquus  Capitis, 
Obturator  Ligament, 

Obturator  Externus,       <-•••';         -  -  -^         -  450 

'Obturator  Internus,  - 

Occipito  Vertebral  Articulation,  270 

Occiput,  -  127 

Occipito -Frontalis, 

Omo-Hyoideus,      -•-•..  "         376 

Opponens  Pollicis,       '**  -  -  431 

Orbits,        -  -  'V|j  !;•*  n      167 

Orbicularis  Oris,  ^^ 

Orbicularis  Palpebrarum,     •  •  .  365 

Orbicular  Ligament,       -.--»-  289 


INDEX.  515 

» 

Page 

Ossification,              .             .             .                          •  .68 

Osteogeny,         .....  67 

Osseous  Part  of  Teeth,         ....  475 

(Esophagus,        .                           .  507 

Ossa  Longa,  Lata,  Crassa,    .  .51 


Palmaris  Longus,      .              .              .              .              .  .421 

Palate,  Soft,        ......  498 

Palmaris  Brevis,        ......         430 

Palate,  Muscles  of,                                                    .  499 

Palate  Bones,            .              .              .              .             .  .140 

Papillae  of  Tongue,         .              .             .             .             .  496 

Papillae  Tactus,  .....         230 

Parotid  Gland,     .              .                            .              .              .  501 

Parietal  Bone,           .             .              .             .              .  .126 

Patella,                 .              .              .              .              .              .  220 

Patella,  Ligaments  of,  .    •     303 

Pectoralis  Major,             .              .              .              .  380 

Pectoralis  Minor,                    .             .             .              .  .381 

Pectinalis,           .                        -  .              .             .             .  445 

Pectineal  Fascia,                    -.              .             .              .  .         438 

Pelvis,  Ligaments  of,                    .             .             .              .  274 

Pelvis,           .              .                           .             .             .  102 

Development  of,    .             .             .             .             .  105 

Mechanism  of,             .              .             .  .106 

Male  and  Female,               .             .             .              .  103 

Pelvic  VertebraR,                     .              .             .             .  .86 

Periosteum  Externum,   .                           .             .              .  63 

Periosteum  Internum,           .             .             .             .  .65 

Perichondrium,  .              .              .              .                           .  254 

Periglottis,    .......         496 

Peroneo-Tibial  Articulations,       ....  307 

Peroneus  Brevis,       .  ...         455 

Peroneus  Longus,             .             .             .             .             .  455 

Peroneus  Tertius,               '    .             .             .             .  .         454 

Pharynx,  Muscles  of,                    .              .              ••."«.  505 

Pharynx,      .              .                            .                          x.  .          504 

Phalanges  of  Hand,         .....  199 

Phalangial  Articulations,        .              .              .'             .  .          298 

Platysma  Myodes  Muscle,           .             .              .  372 

Plica  Polonica,          .             .             .              .              .  .         348 

Plantaris,             ....                           .  457 

Posterior  Ligaments  of  Knee,  ....         303 

Popliteus,                                                                  „  457 

Pronator  Quadratus                .             .             .    •  .         425 

Pronator  Radii  Teres,    .             .              .              .             .  420 

Psoas  Magnus,  ......         398 

Psoas  Parvus,     ......  398 

Pterygoideus  Internus,          .             .              .              .  .         371 


516  INDEX. 

Page 

Pterygoideus  Externus,  -             -            ,            -               370 

Pubic  Ligament,       -  •             •             •                          •        278 

Pulp  of  Tooth,   -.--.-  480 

Pubes,                    "V   •  - 

Pyriformis, 

Pyramidalis, 

Quadratus  Femoris,  -                           -                450 

Quadratus  Lumborum,  -                          -                          -         397 

Radio-Carpal  Articulation,  #                                                       292 

Radio-Ulnar  Articulation,  -                                                             291 

Radius,-                           *  -                        --^                          191 

Rectus  Abdominis,   -  -                          ••«* 

Rectus  Capitis, 

Rectus  Capitis  Posticus,  -             -                                                  409 

Rectus  Femoris,     - 

Rete  Mucosum,        - 

Rhomboideus  Major,      -  -            -,                                         403 

Rhomboideus  Minor,  ....                       403 

Ribs,      -  -                                                       107 

Ribs,  Articulation  of,  278 

Round  Ligament,             -  -                                         300 

Sacrum,        -  -             -             -                          -           86 

Sacro-Iliac  Ligament,      -  276 

Sacro-Spinous  Ligament,  -            -          -XT* 

Sacro-Lumbalis,  |  -                          -                              404 

Sacciform  Ligament,  310 

Salivary  Glands,              -  501 

Sartorius,      -  -                       ;   .» •  •                   442 

Scalenus  Anticus,            -  -           '•*             -             -               k379 

Scalenus  Medius,      -  -          -«.                                              379 

Scalenus  Posticus,  -                           -  '                           380 

Scaphoides,  226 

Scapula,  183 

Scarpa  on  Bones,      -  •<  ~                                                               60 

Scapulo-Humeral  Joint,  -             *  '                                         287 

Sciatic  Ligament,     -  -                                                 276 

Sesamoid^Bones,             -  -             -                                  201,  233 

Semi-Lunar  Cartilages,  •*'            -           '•""'                                 305 

Semilunare,'        -          '  -*  •'             *             -              -                 194 

Sebaceous  Organs,   -  -             -^                         •                       340 

Serosity,                          -  -                            324 

Semi-spinalis  Cervicis,  -             -                                   407 

Semi-spinalis  Dorsi,        *  *'*  -                                         408 

Semi-membranosus,  •                                                             452 

Semi-tendinosus,            "•.,  -            -,:f           451 

Sella  Turcica,           ^   -     I;.*''         -^         -  W1         -         159 


INDEX.  517 

Page 

Serratus  Magnus,  .             .             .                382 

Serratus  Inferior  Posticus,  -                           ...         402 

Serratus  Superior  Posticus,  .             .                403 

Shoulder,     -  -             -             -         182 

Shoulder,  Articulations  of,  -             .                283 

Shape  of  Muscles,  .        .      .         259 

Shoulder,  Motions  of,  .                             204 

Shoulder,  Muscles  of,  414 

Skin,  .             .            328 

Skeleton,  Anatomy  of,    -  -             -                  49 

Soleus,  .             .             .         456 

Sphenoides,         -  ....                   133 

Spinalis  Dorsi,  -  ...                405 

Spine,  .                         78 

Spine,  Uses  of,  -  ...                 90 

Spine,  Ligaments  of,  -                       266 

Splenius,  404 

Spongiosum  Inferius,  .             -                       145 

Stearin,  -  .             .                326 

Stenos  Duct,  .             -             -          502 

Sternum,  -                             111 

Sterno-Cleido  Mastoideus,  -                                                                372 

Sterno-Hyoideus,  -                             375 

Sterno-Tliyroideus,  -                          375 

Stylo-Glossus,  -             -                      377 

Stylo-Pharyngeus,  -                             377 

Stylo-Maxillary  Ligament,  -                                                               264 

Subs  cap  ularis,     -  ...              416 
Subclavius,       .......         382 

Sublingual  Gland,  503 

Submaxillary  Gland,  -       ,      -                                     502 

Supinator  Rad.  Long.,    -  -                             425 

Supinator  Rad.  Brev.,  -                           -                      428 

Supra  Spinatus,              -  -                                           415 

Sutures,  Formation  of,  154 

Sutures,  Uses  of,  -             -                              152 

Sutures,        -  -                           -                                    149 

Symphysis  Pubis,  .                                        •  277 

Synovial  Capsules,  ....                       261 


Temporal  Bone,       -  130 

Thorax,                             -  -                             107 

Articulations  of,  -                                        -       -  278 

Development  of,  1 15 

Mechanism  of,  -                                    116 

Triquetra,          •            •  -            -            -            -               155 


518  INDEX. 

Page 

Tarsus,         - 

Tarso-Metatarsal  Articulation,    -  314 

Teeth,                        -  471 

Formation  of,  479 

Temporalis,  370 

Tendons,             -  -             -                                         360 

Teres  Major,  416 

Teres  Minor,      -  415 
Tensor  Vagina?,        ------         442 

Thumb,  Articulations  of,  -                298 

Thyreo-Hyoideus  Muscle,  -                                                             375 

Thigh,  Motions  of,  241 

Muscles  of,    -  -             -                                                  442 

Tibia,     -------  217 

Tibialis  Posticus,      -  -                                                  459 

Tibialis  Anticus,  453 

Toes,  Bones  of,  -             -             -             -                       232 

Joints  of,     -  -       ,                       315 

Tongue,  -                                                             493 

Mucous  Covering  of,        -  495 

Muscles  of,   -  493 

Trachelo  Mastoideus,      -  407 

Transversalis  Abdominis,  -             -                                                  387 

Transversalis  Cervicis,    -  406 

Transversalis  Pedis,  463 

Transverse  Ligament,     -  272 

Trapezoid  Lig.,  285 

Trapezium,  194 

Trapezius,        -  401 

Triceps  Extensor  Cubiti,  419 

Triceps  Surae,  ...                           -        456 

Triangularis  Sterni,  383 

Triangular  Lig.,  -             -                                                  286 

Trunk,  -                                                        78 

Muscles  of,  -             -             *             *                       400 


Ulna,            -             ,             -             ,             -  -                      189 

Unguis,               ,             .             .             .             -  143 

Upper  Extremities,  182 

Articulations  of,  283 

Development  of,  -                       201 

Mechanism  of,  202 

Muscles  of,  41 1 


Vastus  Externus,  443 

Vastus  Interims,        -  443 

Vertebra,  -                                      -                 78 

Development  of,  •                                       •                        89 

Motions  of,     -  93 


INDEX.  519 

Page 

Vertebral  Ligaments,  ...         266 

Vincula  Acce'ssoria,  ...               425 

Vomer,  .            -         146 

Wrist,  Articulations  of,  -  -               291 

Zygomaticus  Minor,  .            .         357 

Zygomaticus  Major,  -            .               357 


END  OF  VOL. 


LEA    &    BLANC  HARD, 


HAVE  RECENTLY  PUBLISHED, 

MIDWIFERY     ILLUSTRATED, 

BY  FRANCIS  H.  RAMSBOTHAM,  M.D., 

PHYSICIAN  TO  THE  ROYAL  MATERNITY  CHARITY,  AND  LECTURER  ON  MIDWIFERY  AT  THE 
LONDON  HOSPITAL,  ETC. 

THE  PRINCIPLES  AND  PRACTICE 

OF 

OBSTETRIC    MEDICINE    AND    SURGERY, 

IN  REFERENCE  TO  THE 

Process  of  Parturition, 

ILLUSTRATED  BY  ONE  HUNDRED  AND  FORTY-TWO  FIGURES. 

FIRST  AMERICAN  EDITION,  REVISED. 

In  one  large  octavo  volume. 

From  among  numerous  commendations  of  this  work  of  Dr.  Ramsbotham,  the  American 
publishers  append  a  few,  and  would  particularly  call  the  attention  of  the  medical  public  to 
the  execution  of  the  numerous  plates,  which  form  a  most  important  feature  in  the  volume. 
The  great  expense  they  have  incurred  in  its  production  calls  for  an  extended  sale,  which  they 
trust  the  merits  of  the  work  will  command. 

"  It  is  a  good  and  thoroughly  practical  treatise  ;  the  different  subjects  are  laid  down  in  a  clear  and 
perspicuous  form,  and  whatever  is  of  importance  is  illustrated  by  first  rate  engravings.  As  a  work  convey- 
ing good,  sound,  practical  precepts,  and  clearly  demonstrating  the  doctrines  of  obstetrical  science,  we  can 
confidently  recommend  it  either  to  the  student  or  practitioner."  —  Edinburgh  Journal  of  Medical  Science. 

"  It  is  the  book  on  Midwifery  for  students:  clear,  but  not  too  minuto  in  its  details,  and  sound  in  its  prac- 
tical instructions.  It  is  so  completely  illustrated  by  plates  (admirably  chosen  and  executed)  that  the  stu- 
dent must  be  stupid  indeed  who  does  not  understand  the  details  of  this  branch  of  the  science,  so  far  al  least 
as  description  can  make  them  intelligible."  —  Dublin  Journal  of  Medical  Science. 

"There  is  so  much  in  the  practice  of  Midwifery  which  cannot  be  understood  without  pictorial  illustra- 
tions, that  they  become  almost  essential  to  the  student;  but  hitherto  the  expense  has  proved  an  impediment 
to  their  being  employed  so  much  as  desirable.  The  work  has  only  to  be  known  to  make  the  demand  for  it 
very  extensive."  —  Medical  Gazette. 

"  We  strongly  recommend  the  work  of  Dr.  Ramsbotham  to  all  our  obstetrical  readers,  especially  to  those 
who  are  entering  upon  practice.  It  is  not  only  one  of  the  cheapest,  but  one  of  the  most  beautiful  works  in 
Midwifery."—  British  and  Foreign  Medical  Review. 

"  We  feel  much  pleasure  in  recommending  to  the  notice  of  the  profession  one  of  the  cheapest  and  most 
elegant  productions  of  the  medical  press  of  the  present  day.  The  text  is  written  in  a  clear,  concise,  anil 
simple  style.  We  offer  our  most  sincere  wishes  that  the  undertaking  may  enjoy  all  the  success  which  it  so 
well  merits."—  Dublin.  Medical  Press. 

"  We  most  earnestly  recommend  this  work  to  the  student,  who  wishes  to  acquire  knowledge,  and  to  the 
practitioner  who  wishes  to  refresh  his  memory,  as  a  most  faithful  picture  of  practical  Midwifery;  and  we 
can  with  justice  say,  that  altogether  it  is  one  of  the  best  books  we  have  read  on  the  subject  of  obstetrical 
medicine  and  surgery."  —  Medico-  Chirurgical  Review. 

"  It  is  intended  expressly  for  students  and  junior  practitioners  in  Midwifery;  it  is  therefore,  as  it  ought 
to  be,  elementary,  and  will  not,  consequently,  admit  of  an  elaborate  and  extended  review.  Our  chief 
object  ROW  is  to  state  our  decided  opinion,  that  this  work  is  by  far  the  best  that  has  appeared  in  this 
country,  for  those  who  seek  practical  information  upon  Midwifery,  conveyed  in  a  clear  and  concise  style. 
The  value  of  the  work,  too,  is  strongly  enhanced  by  the  numerous  and  beautiful  drawings,  by  Bagg,  which 
are  in  the  first  style  of  excellence.  Every  point  of  practical  importance  is  illustrated,  that  requires  the 
aid  of  the  engraver  to  fix  it  upon  the  mind,  and  to  render  it  clear  to  the  comprehension  of  the  student."— 
London  Medical  Gazette. 

"  Among  the  many  literary  undertakings  with  which  the  Medical  press  at  present  teems,  there  are  few 
that  deserve  a  warmer  recommendation  at  our  hands  than  the  work—  we  might  almost  say  the  obstetrical 
library,  comprised  in  a  single  volume—  which  is  now  before  us.  Few  works  surpass  Dr.  Ramsbotham's  in 
beauty  and  elegance  of  getting  up,  and  in  the  abundant  and  excellent  engravings  with  whiefh  it  is  illus- 
trated. We  heartily  wish  the  volume  the  success  which  it  merits,  and  we  have  no  doubt  that  before  long  it 
will  occupy  a  place  in  every  medical  library  in  the  kingdom.  The  illustrations  are  admirable;  they  are  the 
joint  production  of  Bagg  and  Adlard;  and  comprise,  within  the  series,  the  best  obstetrical  plates  of  our 
best  obstetrical  authors,  ancient  and  modern.  Many  of  the  engravings  are  calculated  to  fix  the  eye  aa 
much  by  their  excellence  of  execution  and  their  beauty  as  works  of  art,  as  by  their  fidelity  to  nature  and 
anatomical  accuracy  :'—Tkt  Lancet. 


THE  PRACTICE  OF  MEDICINE, 

OR  A 

TREATISE  ON  SPECIAL  PATHOLOGY  AND  THERAPEUTICS. 

BY  ROBLEY  DUNGLISON,  M.D., 

PROFESSOR  OF  THE  INSTITUTES  OF  MEDICINE,  ETC.  IN  THE  JEFFERSON  MEDICAL  COLLEGE, 

PHILADELPHIA,  LECTURER  ON  CLINICAL  MEDICINE,  AND  ATTENDING 

PHYSICIAN  AT  THE  PHILADELPHIA  HOSPITAL,  ETC. 

CONTAINING 

THE  DISEASES  OF  THE  ALIMENTARY  CANAL, 
THE  DISEASES  OF  THE  CIRCULATORY  APPARATUS, 

DISEASES  OF  THE  GLANDULAR  ORGANS, 
DISEASES  OF  THE  ORGANS  OF  THE  SENSES, 

DISEASES  OF  THE  RESPIRATORY  ORGANS, 
DISEASES  OF  THE  GLANDIFORM  GANGLIONS, 

DISEASES  OF  THE  NERVOUS  SYSTEM, 

DISEASES  OF  THE  ORGANS  OF  REPRODUCTION, 

DISEASES  INVOLVING  VARIOUS  ORGANS, 

&x.  &c. 

In  Two  Volumes  Octavo. 

"This  new  work,  from  the  press  of  Lea  and  Blanchard,  forms  a  valuable  addition  to  our  Medical 
Literature,  and  fills  up  avoid  in  our  libraries,  which  the  numerous  improvements  in  medical  science 
had  long  since  created ;  and  we  congratulate  the  profession  in  being  put  in  possession  of  a  work  on  the 
practice  of  medicine,  in  which  not  only  are  found  the  latest  and  most  approved  views  of  Pathology, 
united  with  the  soundest  practical  deductions,  but  which  is  here  interspersed  throughout  with  the 
most  valuable  recipes  for  administering  the  various  medicines  suggested. 

"The  object  of  the  author  has  been,  as  he  states,  to  incorporate  the  improvements  and  modifications 
incessantly  taking  place  in  the  departments  of  Pathology  and  Therapeutics,  so  as  to  furnish  those  to 
whom  the  different  general  treatises,  monographs  and  periodicals  are  not  accessible,  with  the  means 
of  appreciating  their  existing  condition.  The  examination  we  have  made  of  the  work  satisfies  us 
that  in  this  aim  he  has  been  eminently  successful,  and  that  he  has  presented  to  the  profession  the 
most  complete  work  on  the  Practice  of  Medicine  to  be  found  in  any  language — for  we  know  of  no 
similar  work  in  which  is  embodied  such  an  amount  of  scientific  and  practical  information.  INo  one, 
therefore,  who  desires  to  keep  himself  au  nouveau  du  siecle,  will  fail  to  include  in  his  collection  a 
work  which  thus  brings  before  him  the  latest  views  of  subjects,  in  which  scientific  investigations 
have  lately  wrought  so  many  changes. 

"This  is  not  the  place  of  course,  to  speak  in  detail  of  the  merits  of  such  a  work.  We  may  there- 
fore say  that  the  two  volumes  before  us  give  evidence  throughout  of  extensive  research,  deep  reflec- 
tion, and  abilities  for  which,  indeed,  the  author's  name  is  always  a  guarantee;  and  that  we  can  con- 
fidently recommend  them  to  all  who  desire  to  keep  pace  with  the  progress  of  medical  science." — 
Bait.  Pat. 

"  We  hail  the  appearance  of  this  work,  which  has  just  been  issued  from  the  prolific  press  of 
Messrs.  Lea  &,  Blanchard,  of  Philadelphia,  with  no  ordinary  degree  of  pleasure.  Compri.-ed  in  two 
large  and  closely  printed  volumes,  it  exhibits  a  more  full,  accurate,  and  comprehensive  digest  of  the 
existing  state  of  medicine  than  any  other  treatise  with  which  we  are  acquainted  in  the  English 
language.  It  discusses  many  topics — some  of  them  of  great  practical  importance,  whuch  are 
entirely  omitted  in  the  writings  of  Eberle,  Dewees,  Ilosack,  Graves,  Stokes,  Mclntosh,  and 
Gregory ;  and  it  cannot  fail,  therefore,  to  be  of  great  value,  not  onlv  to  the  student,  but  to  the 
practitioner,  as  it  affords  him  ready  access  to  information  of  which  he  stands  in  daily  need  in  the 
exercise  of  his  profession,  It  has  been  the  desire  of  the  author,  well-known  as  one  of  the  most 
abundant  writers  of  the  age,  to  render  his  work  strictly  practical ;  and  to  this  end  he  has  been 
induced,  whenever  opportunity  offered,  to  incorporate  the  results  of  his  own  experience  with  that 
of  his  scientific  brethren  in  America  and  Europe.  To  the  former,  ample  justice  seems  to  have  been 
done  throughout.  We  believe  this  constitutes  the  seventh  work  which  Professor  Dunglison  has 
published  within  the  last  ten  years  ;  and,  when  we  reflect  upon  the  large  amount  of  labour  and 
reflection  which  must  have  been  necessary  in  their  preparation,  it  is  amazing  how  he  could  have 
accomplished  so  much  in  so  short  a  time." — Louisville  Journal. 

"  As  a  system  of  Practical  Medicine,  this  work  will  meet  a  cordial  welcome  from  all  who  know 
the  untiring  assiduity  and  laborious  habits  in  the  pursuit  of  knowledge,  of  the  author,  who  has 
already  presented  the  public  with  numerous  excellent  works,  bearing  the  stamp  of  originality  as 
well  as  of  profound  research. 

"  The  object  of  Professor  Dunglison  is  to  present,  in  as  compact  a  form  as  was  consistent  with 
accuracy  and  perspicuity,  a  history  of  all  the  affections  which  properly  come  under  the  care  pt 
the  physician,  with  all  the  improvements  and  modifications  which  have  taken  place  latterly  in 
Pathology  and  Therapeutics,  so  as  to  enable  the  student  and  practitioner  '  to  appreciate  their  present 
condition,'  and  to  avail  themselves  of  knowledge  scattered  about  in  various  journals  and  mono- 
graphs. 

"This  task  has  been  faithfully  executed,  and  the  work  maybe  recommended  as  a  good  class-book, 
in  which  the  soundness  of  the  author's  views  and  his  freedom  from  exclusive  opinions  have  enabled 
him  to  select  from  the  experience  of  others  those  facts  and  views,  which,  together  with  his  own 
experience,  were  to  furnish  the  proper  data  for  correct  descriptions  and  for  sound  practical  deduc- 
tions."— New  York  American, 


LEA    AND    BLANCHARD 

HAVE  JUST  PUBLISHED 

A   NEW   AND   CHEAPER   EDITION 

OP 

THE   LIBRARY 

OF 

PRACTICAL     MEDICINE: 

CONDUCTED  BY 

ALEXANDER  TWEEDIE,  M.D.,  F.R.S. 

PHYSICIAN  TO  THE  LONDON  FEVER  HOSPITAL,  AND  TO  THE  FOUNDLING  HOSPITAL  ;   EDITOR  OF  THE 
CYCLOPEDIA  OF  PRACTICAL  MEDICINE,  ETC. 

WITH  THE  ASSISTANCE  OF  NUMEROUS  CONTRIBUTORS. 

THE  WHOLE  REVISED,  WITH  NOTES  AND  ADDITIONS, 
BY 

W.  W.  GERHARD,  M.D., 

LECTURER  ON  CLINICAL  MEDICINE  TO  THE  UNIVERSITY  OF  PENNSYLVANIA,  PHYSICIAN  TO 
THE  PHILADELPHIA  HOSPITAL,  BLOCKLEY,  ETC. 

The  whole  Five  Volumes  of  the  former  edition,  now  complete  in  Three  large 

Volumes, 

AND  FOR  SALE  BY  ALL  BOOKSELLERS. 

The  design  of  this  work  is  to  supply  the  want,  generally  admitted  to  exist  in  the  medical 
literature  of  Great  Britain,  of  a  comprehensive  System  of  Medicine,  embodying  a  condensed, 
yet  ample,  view  of  the  present  state  of  the  science.  The  desideratum  is  more  especially  felt  by 
the  Medical  Student,  and  by  many  Members  of  the  Profession,  who,  from  their  avocations  and 
other  circumstances,  have  not  the  opportunity  of  keeping  pace  with  the  more  recent  improve- 
ments  in  the  most  interesting  and  useful  branch  of  human  knowledge.  To  supply  this  defi- 
ciency, is  the  object  of  THE  LIBRARY  OF  MEDICINE  ;  and  the  Editor  expresses  the  hope,  that 
with  the  assistance  with  which  he  has  been  favoured  by  Contributors,  (many  of  great  eminence, 
and  all  favourably  known  to  the  Public,)  he  has  been  able  to  produce  a  work,  which  will  form 
a  Library  of  General  Reference  on  Theoretical  and  Practical  Medicine,  as  well  as  a  Series  of 
Text  Books  for  the  Medical  Student. 

It  is  intended  to  treat  of  each  Department,  or  Division  of  Medicine,  each  SERIES  forming  a 
complete  Work  on  the  subject  treated  of,  which  may  be  purchased  separately  at  a  very  mode- 
rate price,  or  it  will  constitute  a  part  of  THE  LIBRARY  OF  MEDICINE.  This  arrangement  is 
made  with  the  view  of  giving  those  persons  who  may  wish  to  possess  ONE  OR  MORE  OF  THE 
SERIES,  the  opportunity  of  purchasing  such  Volumes  only,  and  thus  avoid  the  inconvenience 
of  making  a  larger  addition  to  their  stock  of  Books  than  their  wants  or  circumstances  may 
require. 

Each  treatise  is  authenticated  by  the  Name  of  the  Author  ;  and  from  the  care  bestowed  in 
the  arrangements,  it  is  confidently  hoped  that  the  want  of  uniformity  noticed  in  works  of  a 
similar  kind,  has  been  obviated,  at  least,  as  far  as  is  compatible  with  the  execution  of  the  work 
by  a  numerous  body  of  united  Authors. 


ADVERTISEMENT 

OF 

THE  AMERICAN  PUBLISHERS  TO  THEIR  NEW  EDITION 
IN  THREE  VOLUMES. 


The  matter  embraced  in  the  Three  Volumes  now  presented,  was  published  in  London  in 
five  separate  volumes,  and  at  intervals  republished  in  this  country.  The  rapid  sale  of  these 
volumes,  embracing  as  they  do  a  History  of  Practical  Medicine,  is  the  best  evidence  of  the 
favour  with  which  it  has  been  received  by  the  physicians  of  the  United  States.  Embodying 
as  it  does  the  most  recent  information  on  nearly  every  disease,  and  written  by  men  who 
have  specially  devoted  themselves  to  the  study  of  the  disorders  which  form  the  subject  of 
their  articles,  the  work  is  the  most  valuable  for  reference  within  the  reach  of  a  practitioner. 
The  arrangement  of  the  Library  into  classes  of  diseases,  grouped  according  to  the  cavities  of 
the  body,  is  much  more  agreeable  to  the  reader  than  the  alphabetical  order,  and  nearly  as 
convenient  for  reference. 

The  reader  will  not  fail  to  perceive  some  inequality  in  the  articles,  even  of  the  same 
authors ;  the  subjects  with  which  an  author  is  most  familiar,  and  upon  which  he  had  pre- 
viously written,  are  usually  the  best  treated  and  most  elaborate.  Among  the  most  finished 
treatises  are  those  of  Dr.  Christison  on  the  urinary  organs,  and  of  Williams  and  Joy  on  the 
thoracic  viscera ;  several  other  essays  are  excellent  monographs,  and  very  few  fall  much 
below  the  average  standard  of  the  series. 

The  object  of  the  publishers  in  compressing  the  five  volumes  of  the  former  edition  into  three 
is  to  place  the  work  at  such  a  price  as  to  be  within  the  reach  of  every  reader.  There  is  no 
abridgement  or  alteration  whatever  of  the  text  of  the  former  edition,  and  the  general  ap- 
pearance of  the  volumes  is  scarcely  inferior.  The  notes  added  to  the  last  four  volumes  have 
been  revised,  and  some  additions  made  to  them.  New  notes  have  also  been  added  to  the  first 
volume,  which  was  not  revised  in  the  former  edition.  For  the  note  on  Remittent  Fever,  the 
American  Editor  is  indebted  to  Dr.  Stewardson,  for  those  on  Ophthalmia  to  Dr.  W.  P.  Johnston. 
The  principal  notes  are  one  on  Typhoid  Fever,  another  on  Remittent,  one  on  Tuberculous 
Meningitis,  and  a  fourth  on  Delirium  Tremens.  It  was  neither  intended  nor  wished  to  over- 
load the  work  with  annotations ;  the  notes  refer  either  to  some  trivial  errors  which  have  crept 
into  the  text,  or  to  subjects  which  were  treated  less  completely  than  they  deserved  to  be ;  they 
are,  therefore,  comparatively  few  in  number.  Several  diseases  are,  from  the  difference  of  cli- 
mate, more  frequent  and  severe  in  the  United  States  than  in  Great  Britain,  and  the  articles 
which  relate  to  them  required  some  additional  matter. 

The  notes  which  appeared  in  the  London  edition  are  designated  by  the  word  Author.  Those 
of  the  American  Editor  are  indicated  by  the  letter  G. 

The  Editor  of  this  edition  did  not  feel  himself  at  liberty  to  make  any  change  in  the  for- 
mulas of  the  prescriptions,  which  are  published  towards  the  end  of  the  last  volume,  believing, 
as  he  does,  that  very  strong  reasons  alone  can  justify  such  use  of  a  scientific  work.  One 
alteration,  which  adapts  them  to  the  custom  of  this  country,  was,  however,  made ; — that  is,  the 
translation  of  the  directions  for  the  doses  and  administration  of  the  prescriptions  from  Latin 
into  English :  there  is  an  obvious  convenience  in  this  change. 

The  Three  Volumes  now  presented  contain  the  first  series,  that  on  Practical  Medicine,  of  a 
Library  of  Medicine,  edited  by  Dr.  Tweedie,  and  now  in  course  of  publication,  and  are  com- 
plete in  themselves.  The  series  will  be  continued  in  London,  embracing  works  on  Midwifery,* 
Surgery,  Anatomy,  and  the  other  Departments  of  Medical  Science.  Such  of  them  as  may  be 
deemed  worthy  of  republication  will  be  issued  here  with  notes  and  additions,  each  work  under 
its  particular  title,  but  in  a  style  and  manner  to  match  this  work. 

*  The  work  on  Midwifery,  by  Edward  Rigby,  with  numerous  wood  cuts,  has  lately  been  issued  by  the  pub- 
lishers of  these  volumes. 


LEA  &  BLANCHARD, 

PHILADELPHIA, 

HAVE    RECENTLY    PUBLISHED 
A  NEW  SERIES  OF 

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JOURNAL  OF  THE  MEDICAL  SCIENCES, 

EDITED  BY 

ISAAC  HAYS,  M.  D. 

COMMENCED  ON  THE  JST  OF  JANUARY,  1841. 

TERMS. 

Each  number  contains  260  pages,  or  upwards,  and  is  frequently  illustrated  by  coloured 
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PRACT ICAL 

GEOLOGY   AND   MINERALOGY, 

WITH   INSTRUCTIONS  FOR 

THE    QUALITATIVE 

ANALYSIS   OF   MINERALS. 

BY  JOSHUA  TRIMMER,  F.G.S. 

WITH   212   WOOD    CUTS. 

A  handsome  Octavo  Volume  bound  in  Embossed  cloth. 

This  is  a  systematic  introduction  to  Mineralogy  and  Geology,  and  admirably  calculated  to 
instruct  the  student  in  those  sciences.  The  organic  remains  of  the  various  formations  are 
well  illustrated  by  numerous  figures  which  are  drawn  with  great  accuracy. 


THE  BRIDGEWATER  TREATISES,  COMPLETE  IN  SEVEN  VOLS.,  OCTAVO. 

EMBRACING, 

I.  The  Adaptation  of  External  Nature  to  the  Moral  and  Intellectual  Constitution  of  Man. 
By  the  Rev.  Thomas  Chalmers. 

II.  The  Adaptation  of  External  Nature  to  the  Physical  Condition  of  Man.     By  John  Kidd, 
M.  D.,F.R.S. 

III.  Astronomy  and  General  Physics,  considered  with   Reference  to  Natural  Theology. 
By  the  Rev.  William  Whewell. 

IV.  The   Hand  :    Its  Mechanism  and  Vital   Endowments  as  Evincing  Design.     I>y  Sir 
Charles  Bell,  K.  H.,  F.  R.  S.     With  numerous  wood  cuts. 

V.  Chemistry,  Meteorology,  and   the  Function  of  Digestion.     By   Wm.  Prout,  M.  D., 
F.  R.  S. 

VI.  The  History,  Habits,  and  Instincts  of  Animals.     By  the  Rev.  William  Kirby,  M.  A., 
F.  R.  S.     Illustrated  by  numerous  engravings  on  copper. 

VII.  Animal  and  Vegetable  Physiology,  considered  with  Reference  to  Natural  Theology. 
By  Peter  Mark  Roget,  M.  D.     Illustrated  with  nearly  Five  Hundred  Wood  Cuts. 

VIII.  Geology  and  Mineralogy,  considered  with  Reference  to  Natural  Theology.     By  the 
Rev.  William  Buckland,  D.  D.     With  numerous  engravings  on  copper,  and  a  large  coloured 
Map. 

ICT  The  work  of  BUCKLAND,  KIRBY  and  ROGET,  may  be  had  separate. 


THIRD  EDITION  BROUGHT  UP  TO  1841, 

OF 

NEW  REMEDIES. 

THE  METHOD  OF  PREPARING  AND  ADMINISTERING  THEM; 

THEIR  EFFECTS 

UPON  THE 

HEALTHY  AND  DISEASED  ECONOMY,  &c.  &c. 

BY  ROBLEY  DUNGLISON,  M.  D. 

Professor  of  the  Institutes  of  Medicine  and  Materia  Medico,  in  Jefferson  Medical  College  of 
Philadelphia;  Attending  Physician  to  the  Philadelphia  Hospital,  Sfc. 

IN  ONE  VOLUME,  OCTAVO. 

[Extract  from  the  Preface  to  the  Third  Edition.] 

"  This  edition  has  been  subjected  to  an  entire  revision,  and  the  author  has  modified  in  cer- 
tnin  respects  the  arrangement,  and  altered  the  nomenclature  so  as  to  cause  it  to  correspond 
more  nearly  to  that  adopted  in  the  Pharmacopoeia  of  the  United  States." 


THIRD  EDITION  BROUGHT  UP  TO  1842, 

OF 

DUNGLISON'S  DICTIONARY 

OF 

MEDICAL   SCIENCE   AND   LITERATURE: 

CONTAINING 

A  concise  account  of  the  various  Subjects  and  Terms,  and  formula  for  various  officinal  and 

empirical  preparations,  fyc. 

IN  ONE  ROYAL  OCTAVO  VOLUME. 

This  new  Edition  includes  in  -the  body  of  the  work,  The  Index,  or  Vocabulary  of  Syno- 
nytnes  that  was  in  the  former  Editions  printed  at  the  end  of  the  Volume,  and  embraces  many 
corrections,  with  the  additions  of  many  new  words. 


FOURTH  EDITION,  IMPROVED  WITH  ADDITIONS  UP  TO   1842, 


OF 


DUNGLISON'S  HUMAN  PHYSIOLOGY: 

ILLUSTRATED  WITH  NUMEROUS  ENGRAVINGS. 

IN  TWO  VOLUMES  OCTAVO. 


THE  MEDICAL  STUDENT; 

OR,  AIDS  TO  THE  STUDY  OF  MEDICINE. 

Including  a  Glossary  of  the  Terms  of  the  Science,  and  of  the  mode  of  Prescribing;  Biblio- 
graphical Notices  of  Medical  Works;  the  Regulations  of  the  Different 
Medical  Colleges  of  the  Union,  &c. 

BY  ROBLEY  DUNGLISON,  M.  D.,  &c.  &c. 

la  One  Volume,  Octavo. 


THE   FIRST   PRINCIPLES   OF   MEDICINE. 

BY  ARCHIBALD  BILLING,  M.  D.  A.  M. 

Member  of  the  Senate  of  the  University  of  London,  Fellow  of  the  Royal  College  of  Physicians, 

$c.  $c. 

In  One  Volume,  8vo.     First  American  from  the  Fourth  London  Edition. 
"We  know  of  no  book  which  contains  within  the  same  space  so  much  valuable  informa- 
tion, the  result  not  of  fanciful  theory,  nor  of  idle  hypothesis,  but  of  close  persevering  clinical 
observation,  accompanied   with    much  soundness   of  judgment,  and  extraordinary  clinical 
tact." — Medico-Chirurgical  Review. 

A  NEW  EDITION  (THE  SIXTH)  OF 

THE  MEDICAL  FORMULARY  OF  DR.  ELLIS, 

This  edition  is  completely  revised,  with  many  additions  and  modifications,  and  brought  up  to 
the  present  improved  state  of  the  Science, 

BY  SAMUEL  GEORGE  MORTON,  M.  D. 
Professor  in  the  Pennsylvania  College  of  Medicine,  fyc.  &c. 


A  PRACTICAL  TREATISE  ON  THE  HUMAN  TEETH, 

Showiflg  the  causes  of  their  destruction  and  the  means  of  their  preservation.     By  VVm. 

Robertson.     With  plates.     First  American,  from  the  second  London 

edition.     In  One  Volume. 


OUTLINES   OF  A 
COURSE  OF  LECTURES  ON  MEDICAL  JURISPRUDENCE. 

BY  THOMAS  STEWART  TRAILL,  M.  D. 
From  the  Second  Edinburgh  Edition,  with  American  Notes  and  Additions. 


ARNOTT'S  ELEMENTS  OF  PHYSICS. 

Complete  in  One  Volume. 

A  New  Edition  of  Elements  of  Physics,  or  Natural  Philosophy,  general  and  medical,  writ- 
ten  for  universal  use,  in  plain  or  non-technical  language,  and  containing  New  Disquisitions 
and  Practical  Suggestions,  comprised  in  five  parts:— 1st.  Sornatology,  Statics  and  Dynamics. 
2d.  Mechanics.  3d.  Pneumatics,  Hydraulics  and  Acoustics.  4th.  Heat  and  Light.  5th. 
Animal  and  Medical  Physics.  Complete  in  one  volume,  by  Neil  Arnott,  M.  D.,  of  the  Royal 
College  of  Physicians.  A  new  edition,  revised  and  corrected  from  the  last  English  edition, 
with  additions,  by  Isaac  Hays,  M.  D. 

A  PRACTICE  OF  PHYSIC. 

Comprising  most  of  the  diseases  not  treated  of  in  Diseases  of  Females  and  Diseases  of 
Children,  second  edition.  By  VV.  P.  Dewees,  M.  D.,  formerly  adjunct  professor  in  the  Uni- 
versity of  Pennsylvania.  Iu  one  volume,  octavo. 


A  COMPENDIOUS    SYSTEM    OF    MIDWIFERY. 

BY  DR  DEWEES. 

Chiefly  designed  to  facilitate  the  Inquiries  of  those  who  may  be  pursuing  this  branch  of 
study.  Illustrated  by  occasional  cases  and  with  many  plates.  The  ninth  edition,  with  addi- 
tions and  improvements.  In  one  vol.  8vo. 


DEWEES  ON  THE  DISEASES  OF  FEMALES. 

The  seventh  Edition,  Revised  and  Corrected.     With  Additions  and  Numerous  Plates. 
In  One  Vol.,  8vo. 


DEWEES  ON  THE  PHYSICAL  AND  MEDICAL  TREATMENT  OF  CHILDREN 

With  Corrections  and  Improvements.     The  seventh  edition.     In  one  volume,  8vo. 


A  FLORA  OF  NORTH  AMERICA. 
With  108  Coloured  Plates.    By  W.  P.  C.  Barton,  M.  D.    In  three  volumes,  quarto. 


A  Treatise  on  Special  and  General  Anatomy.  By  W.  E.  Horner,  M.  D.,  Professor  of  Ana- 
tomy  in  the  University  of  Pennsylvania,  &c.,  &c.  Fifth  edition,  Revised,  and  much  im- 
proved. In  two  volumes,  8vo. 

This  work  is  extensively  used  as  a  Text  Book. 


A  System  of  Midwifery,  with  numerous  wood  cuts,  by  Edward  Rigby,  M.  D.,  Physician  to 
the  General  Lying-in  Hospital,  Lecturer  on  Midwifery  at  St.  Bartholomew's  Hospital,  &c., 
with  notes  and  additional  illustrations  by  an  American  Practitioner.  In  One  Volume. 

Extract  from  the  Editor's  Preface. — "This  System  of  Midwifery,  complete  in  itself,  was 
published  in  London,  as  part  of  Dr.  Tweedie's  4  Library  of  Medicine.'  The  first  series  of  the 
Library,  that  on  •  Practical  Medicine,'  recently  completed,  has  been  received  with  extraordi- 
nary favour  on  both  sides  of  the  Atlantic,  and  the  character  of  the  publication  is  fully  sus- 
tained in  the  present  contribution  by  Dr.  Rigby,  and  will  secure  for  it  additional  patronage. 

"The  late  Professor  Dewees,  into  whose  hand  this  volume  was  placed,  a  few  weeks  before 
his  death,  in  returning  it  expressed  the  most  favourable  opinion  of  its  merits,  and  the  judg- 
ment of  such  high  authority  renders  it  supererogatory  to  add  a  word  farther  of  commenda- 
tion." 

A  Treatise  on  Pulmonary  Consumption,  comprehending  an  inquiry  into  the  Nature,  Causes, 
Prevention,  and  Treatment  of  Tuberculous  and  Scrofulous  Diseases  in  General.  By  James 
Clark,  M.  D.,  F.  R.  S.  

Essays  on  ASTHMA,  APHTHA  ASPHYXIA,  APOPLEXY,  ARSENIC,  ATROPA, 
AIR,  ABORTION,  ANGINA-PECTORIS,  and  other  subjects  Embraced  in  the  Articles 
from  A  to  Azote,  prepared  for  the  Cyclopaedia  of  Practical  Medicine.  By  Dr.  Chapman, 
and  others. 

Each  article  is  complete  within  itself,  and  embraces  the  practical  experience  of  its  author, 
and  as  they  are  only  to  be  had  in  this  collection  will  be  found  of  great  value  to  the  profes- 
sion. 

%*  The  two  volumes  are  now  offered  at  a  price  so  low,  as  to  place  them  within  the  reach 
of  every  practitioner  and  student. 

A  Practical  Treatise  on  Medical  Jurisprudence,  with  so  much  of  Anatomy,  Physiology, 
Pathology,  and  the  Practice  of  Medicine  and  Surgery,  as  are  essential  to  be  known  by  Mem- 
bers of  the  Bar  and  Private  Gentlemen;  and  all  the  laws  relating  to  Medical  Practitioners; 
with  explanatory  plates.  By  J.  Chitty,  Esq.  Second  American  edition :  with  Notes  and 
Additions,  adapted  to  American  works  and  Judicial  Decisions,  8vo. 

Abercrombie's  Pathological  and  Practical  Researches  on  Diseases  of  the  Stomach,  the  In- 
testinal Canal,  the  Liver,  and  other  Viscera  of  the  Abdomen.  Third  American,  from  the 
second  London  edition,  enlarged.  In  1  vol.  8vo. 


A  Treatise  on  Fever.     By  Southwood  Smith,  M.  D.,  Physician  to  the  London  Fever  Hos- 
pital.    Fourth  American  edition.     In  I  volume,  8vo. 

The  Anatomy,  Physiology,  and  Diseases  of  the  Teeth.     By  Thomas  Bell,  F.  R.S.,  F.  L.  S., 
&c.,    Third  American  edition.    In  1  vol.  8vo.     With  numerous  plates. 


A  COMPENDIOUS    SYSTEM    OF    MIDWIFERY. 

BY  DR  DEWEES. 

Chiefly  designed  to  facilitate  the  Inquiries  of  those  who  may  be  pursuing  this  branch  of 
study.  Illustrated  by  occasional  cases  and  with  many  plates.  The  ninth  edition,  with  addi- 
tions and  improvements.  In  one  vol.  8vo. 


DEWEES  ON  THE  DISEASES  OF  FEMALES. 

The  seventh  Edition,  Revised  and  Corrected.     With  Additions  and  Numerous  Plates. 
In  One  Vol.,  8vo. 


DEWEES  ON  THE  PHYSICAL  AND  MEDICAL  TREATMENT  OF  CHILDREN 

With  Corrections  and  Improvements.     The  seventh  edition.     In  one  volume,  8vo. 


A  FLORA  OF  NORTH  AMERICA. 
With  108  Coloured  Plates.    By  W.  P.  C.  Barton,  M.  D.     In  three  volumes,  quarto. 


A  Treatise  on  Special  and  General  Anatomy.  By  W.  E.  Horner,  M.  D.,  Professor  of  Ana- 
tomy  in  the  University  of  Pennsylvania,  &c.,  &c.  Fifth  edition,  Revised,  and  much  im- 
proved. In  two  volumes,  8vo. 

This  work  is  extensively  used  as  a  Text  Book. 


A  System  of  Midwifery,  with  numerous  wood  cuts,  by  Edward  Rig-by,  M.  D.,  Physician  to 
the  General  Lying-in  Hospital,  Lecturer  on  Midwifery  at  St.  Bartholomew's  Hospital,  &c., 
with  notes  and  additional  illustrations  by  an  American  Practitioner.  In  One  Volumo. 

Extract  from  the  Editor's  Preface. — "This  System  of  Midwifery,  complete  in  itself,  was 
published  in  London,  as  part  of  Dr.  Tweedie's  '  Library  of  Medicine.'  The  first  series  of  tho 
Library,  that  on  '  Practical  Medicine,'  recently  completed,  has  been  received  with  extraordi- 
nary favour  on  both  sides  of  the  Atlantic,  and  the  character  of  the  publication  is  fully  sus- 
tained in  the  present  contribution  by  Dr.  Rigby,  and  will  secure  for  it  additional  patronage. 

"The  late  Professor  Dewees,  into  whose  hand  this  volume  was  placed,  a  few  weeks  before 
his  death,  in  returning  it  expressed  the  most  favourable  opinion  of  its  merits,  and  the  judg- 
ment of  such  high  authority  renders  it  supererogatory  to  add  a  word  farther  of  commenda- 
lion." 


A  Treatise  on  Pulmonary  Consumption,  comprehending  an  inquiry  into  the  Nature,  Causes, 
Prevention,  and  Treatment  of  Tuberculous  and  Scrofulous  Diseases  in  General.  By  James 
Clark,  M.  D.,  F.  R.  S.  

Essays  on  ASTHMA,  APHTHA,  ASPHYXIA,  APOPLEXY,  ARSENIC,  ATROPA, 
AIR,  ABORTION,  ANGINA-PECTORIS,  and  other  subjects  Embraced  in  the  Articles 
from  A  to  Azote,  prepared  for  the  Cyclopaedia  of  Practical  Medicine.  By  Dr.  Chapman 
and  others. 

Each  article  is  complete  within  itself,  and  embraces  the  practical  experience  of  its  author, 
and  as  they  are  only  to  be  had  in  this  collection  will  be  found  of  great  value  to  the  profes- 
sion. 

%*  The  two  volumes  are  now  offered  at  a  price  so  low,  as  to  place  them  within  the  reach 
of  every  practitioner  and  student. 

A  Practical  Treatise  on  Medical  Jurisprudence,  with  so  much  of  Anatomy,  Physiology, 
Pathology,  and  the  Practice  of  Medicine  and  Surgery,  as  are  essential  to  be  known  by  Mem- 
bers  of  the  Bar  and  Private  Gentlemen;  and  all  the  laws  relating  to  Medical  Practitioners; 
with  explanatory  plates.  By  J.  Chitty,  Esq.  Second  American  edition :  with  Notes  and 
Additions,  adapted  to  American  works  and  Judicial  Decisions,  8vo. 


Abercrombie's  Pathological  and  Practical  Researches  on  Diseases  of  the  Stomach,  the  In- 
testinal Canal,  the  Liver,  and  other  Viscera  of  the  Abdomen.  Third  American,  Irom  the 
second  London  edition,  enlarged.  In  1  vol.  8vo. 


A  Treatise  on  Fever.     By  Southwood  Smith,  M.  D.,  Physician  to  the  London  Fever  Hos- 
pital.    Fourth  American  edition.     In  I  volume,  8vo. 


The  Anatomy,  Physiology,  and  Diseases  of  the  Teeth.     By  Thomas  Bell,  F.  R.S.,  F.  L.S., 
&c.,    Third  American  edition.    In  1  vol.  8vo.     With  numerous  plates. 


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